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Journal
and Publications
AGING
AND THE MEDITERRANEAN DIET
In
studying mortality statistics from the WHO database between
1960 and 1990, there was evidence that suggested the
Mediterranean population had a healthy lifestyle. It has
been thought that the Mediterranean diet is a significant
component of this healthy lifestyle. In evaluating 3 major
studies, the conclusions are that when individuals adhere to
the principles of the traditional Mediterranean diet, these
individuals experience longer survival. The Greek version of
the Mediterranean diet includes the consumption of olive oil
and a high amount of vegetables and fruits. Antioxidants are
present in these foods. Wild edible greens are eaten
frequently in rural Greece in the form of salads and pies,
which contain high amounts of flavonoids. These amounts of
flavonoids arc considerably higher than those found in red
wine or black tea. Antioxidants may play a role in the
beneficial effect of the Mediterranean diet. In the
Mediterranean diet, antioxidants are found in abundance in
vegetables, fruit, beverages and also virgin olive oil.
“Mediterranean
Diet and Longevity’,” Trichopoulou A, Vasilopou E, Br
J Nutr, 2000;84q”Suppl. 2,):S205-S209. (Address: A.
Trichopoulou,
Dept Hygiene Epidemiol, Univ Athens, Med School, Mikras
Asias 75, Athens 11527, Greece, +301 7488 042, (FAX) +301
7488
902, E-mail: Antonia@nut.uoa.gr) 36979
PEARL:
When you look at the Mediterranean diet pyramid that
is included in this article, the lower half includes the use
of olive oil, 3 servings of fruit and 6 servings of
vegetables per day (including wild greens) and 8 servings
per day of non-refined cereals, such as whole grain breads,
whole grain pastas and brown rice. It also includes 2
servings of dairy products on a daily basis. Additional key
components are drinking a lot of water and avoiding salt and
replacing it with herbs, such as oregano, basil and thyme. A
key observation regarding this study is that the authors
make a point of defining nonrefined cereals and products
versus just lumping all carbohydrates together, and also
place an emphasis on green vegetables and fruit, which I
think is outstanding.
ASTHMA,
FISH OIL AND OMEGA-3 FATTY ACID
Fifteen
children with asthma (mean age of 10.2 years. $ males and 7
females) received between 6 and 12 capsules per day of fish
oil. depending on their weight, compared with 14 subjects (7
males and 7 females) who had bronchial asthma (mean age of
11.9 years) who received a 300 mg olive oil placebo. The
300-mg fish oil capsules contained 84 mg of eicosapentaenoic
acid (EPA) and 36 mg of docosahexaenoic acid (DHA) per
capsule. The fish oil supplementation was implemented for 10
months. The daily dose of EPA and DHA ranged from 17.0 to
26.8 and 7.3 to 11.5 mg/kg body weight. respectively. Asthma
symptom scores were reduced and their response to
acetylcholine decreased in the fish oil group but not in the
control group. Plasma EPA levels increased significantly
only in the fish oil group. There were no side effects seen.
“Dietary
Supplementation With Fish Oil Rich in Omega-3
Polyunsaturated Fatty Acids in Children With Bronchial
Asthn,a,” Nagakura T, Matsuda S, et a!, Eu,r Respir J,
2000;16:861-865. (Address: 1’. Nagakura, Yoga Allergy
Clinic, Greenhouse No. 6-201, 4-11-17,
Yoga, Setagaya-ku, Tokyo,
158-009 7, Tokyo, Japan,
(FAX)
81
354914497) 37043
PEARL:
It has always been implied but there are little data
showing that omega-3 fatty acids can be used to treat asthma
directly. When one looks at the new medications, such as the
leukotriene receptor antagonist, it becomes easy to
understand how the omega-3 fats may work, because they can
displace arachidonic acid which is a precursor to
inflammatory leukotrienes when metabolized into downstream
prostaglandins.
ATROPHIC
GASTRITIS AND POLYUNSATURATED FATTY ACID
In
evaluating 92 individuals with atrophic gastritis (men and
women over 40 years of age), serum levels of ornega-3
polyunsaturated fatty acids, especially docosahexaenoic acid
(DHA). were significantly higher in the atrophic gastritis
group compared with the non-atrophic gastritis group. Levels
of gamma-linolenic acid (GLA) were significantly lower in
the atrophic gastritis group. The odds ratios for high serum
DHA and GLA levels in atrophic gastritis subjects were 2.2))
and 0.34. respectively.
“Effects
of Polyunsaturated Fatty Acids on Atrophic Gastritis in a
Japanese Population,” Ito Y, Suzuki K, Imai H, et al, cancer
Lett 2001;163:1 71-1 78. (Address: Yoshinori Ito, Dept
Public Health, Fujita Health Univ School of Heal!!, Sci,
Dengakugakubo, Kutsukake-cho, Toyoake, Aichi 470-1192,
Japan, (Tel/FAX) +81-562- 93-9405, Email: yoshiito@fujita-hu.ac.jp)
36978
PEARL:
This is an unexpected finding for me. In our present
culture, the omega-3 fatty acids have been thought of as the
“good fats,” whereas the omega-6 fatty acids have been
thought of as the “bad fats.” Docosahexaenoic acid (DHA)
is popularly thought of as one of the beneficial omega-3
fatty acids. The reality is it is the balance of the two
that matters. Indeed, in this study, the balance between
omega-3 and omega-6 fatty acids was important. Gammalinolenic
acid (GLA) levels were low, while DIIA levels were high in
this group of Japanese atrophic gastritis patients. It is
known that the prostaglandins are involved in the protective
mucosal harrier of the gastrointestinal tract. It may be
that GLA is important in maintaining this barrier. GLA
supplementation may be beneficial in preventing atrophic
gastritis in Helicobacter pylori positive subjects. It is
interesting that the Japanese eat the diet that is rich in
fish oil (high in DHA). GLA is found abundantly in plant
seed oils, such as evening primrose, black currant and
borage oil. In this study, serum GLA levels were positively
associated with the consumption of tofu and black tea.
BEHAVIOR.
5-HYDROXYTRYPTOPHAN AND TRY PTOPHAN
In
32 adult male vervet monkeys from 16 different social
groups. trvptophan at 10. 20. and 40 mg/kg day produced a
dose-dependent reduction in aggression. vigilance and
locomotion and increases in eating. In the same animals,
5-hydroxytr~ptophan at 20, 40. and 80/ mg/kg/day resulted in
increased aggression and vigilance and did not
I
affect locomotion or eating. Fluoxetine. a serotonin
reuptake inhibitor. at varying doses produced similar
effects to tryptophan. while desmethylimipramine. which is a
catecholaminc reuptake inhibitor, at varying doses resulted
in dose-dependent increases in aggression. vigilance and
locomotion and reductions in eating. When tryptophan ‘~as
combined with fluoxetine, there was an enhancement of the
effects 4f tryptophan on all behaviors, and when it was
combined with desmethylimipramine. there was a reduction
oftryptophan effects on all behaviors. Fluoxetine decreased
and desmethyl imipramine increased the effects of
5-hydroxytryptophan on aggression and vigilance.
“Differential
Behavioral Effects of Tryplophan and 5-Hydroxytryptophan in
Vervet Monkeys: Influence of Catec/z olantinergic
Systems,” Raleigh Mi, Psych op/,ar,nacology, 198
7;93:44-50. 37109
PEARL:
The last thing I would have thought was that two serotonin
precursors, L-tryptophan and 5-hyd roxytryptophan. would
have different effects on aggression. It has to do with
where these two substances produce their serotonin.
Serotonin formed from tryptophan supplementation is very
similar to that of endogenous tryptophan. while the
serotonin formed by 5-hydroxytrvptophan is produced more
diffusely and includes regions high in catecholaminergic
neurons. The metabolism of 5-hydroxytrvptophan results in
serotonin that can influence catecholamine function b~
displacing catecholamines from storage granules. This may
result in a temporary enhancement of postsynaptic
catecholaminergic stimulation, which may affect behavior in
a more aggressive fashion.
BEHAVIOR.
OLIGOANTIGENIC DIET AND SALICYLATE
In
studying I 4t) children using a modified elimination diet
and challenge protocol that ~ as des sod to manage recurrent
urticaria. 86 of the children had significant impros enicnt.
Of these 86. almost three-quarters reacted in a double-blind
challenge to salicylates but not placebo. There was also a
high frequency of reactions to preservatives, azo-dyes.
Antioxidants, brewer’s yeast. amines and monosodium
glutamate. Most children reacted to between 2 and 5 of the
compounds. The authors noted that these findings supported
the Feingold hypothesis. but also noted that the Feingold
diet does not eliminate salicylates. It is noted that many
different foods can contain the same substances. Individuals
could base multiple food allergy, although to a single
substance in those particular foods. The authors found that
common allergens, such as soy. co~ s milk, wheat, eggs,
peanuts and fish, did not cause the behavior problems that
were produced with salicylate- and amine-containing foods.
Salicylate-containing foods included grapes. oranges.
peanuts. maize, melons, tomatoes, pineapple. apples, pears,
tea, coffee. other nuts.
Salicylate.s’,
Oligoantigenic’ Diets, and Behaviour, “Swain A, Soutter
V, Lobby R, Truswall AS, Lancet, July 6, 1985:41-42.
37105
PEARL:
I am guilty, myself, of saying that an individual has
multiple food intolerances to individual foods, but not
thinking that there may be a common ingredient in the foods
reacted to, such as salicylates or amines, that might be
causing the problem. This is something to definitely
consider. This also implies that the best, but most
time-consuming way to determine these allergies is with an
elimination-challenge diet to assist people with these food
intoIerances.
BONE
LOSS, MENOPAUSE AND SOY PROTEIN
In
85 postmenopausal Japanese women who were 66.9 years of age
with protein intake at 62.5 g/day, calcium intake at 733
mg/day and soy protein intake at 12.6 g/day, 60% were
osteopenic or osteoporotic, with respect to lumbar bone
mineral density. Soy protein intake was significantly
associated with the Z-score for L2-4 bone mineral density
and urinary deoxypyridinoline. Soy protein may have an
estrogen-like effect on bone metabolism, due to its ability
to reduce urinary deoxypyridinoline. which is a marker of
bone resorption. Soy protein contains nutrients, such as
calcium, vitamin K and phytoestrogens. One of these
phytoestrogens, ipriflavone, has been made synthetically,
which inhibits osteoclast recruitment and function, and has
been shown at 600 mg/day to prevent bone loss. This study
showed that higher soy protein intake was associated with
higher bone mineral density and a lower level of bone
resorption.
“Effect
of Soy Protein on Bone Metabolism in Postmen opausal
Japanese Wonien,” Horiuchi T. Onouchi T, Takahashi M, et
al, Osfeoporos mv,
2000;II:721-724. (Address: T. Horiuchi, Dept Endocrino!,
Tokyo Metropolitai: Geriatric Hasp, 35-2 Sakaecho,
Itabashiku, Tokyo, Japan) 36989
PEARL:
Since increased urinary deoxypyridinoline is a sign of
calcium loss from bone, the reduction of this substance in
the urine is a positive indicator for reducing bone loss.
This article notes that soy protein also contains other
nutrients, such as calcium, vitamin K and phytoestrogens.
Ipriflavone is a synthetic isoflavone,
7-isopropexy-isoflavone, which has been used in
well-designed studies at a dose of 600 mg/day and has
reduced bone loss. It is possible that this is part of the
component of soy protein, among other things, that helps
reduce bone loss. Also, Japanese studies have shown that
very large doses in the mg range of vitamin K have actually
improved bone density. When we tr to extrapolate the use of
soy protein and the variety of potential benefits, I think
we should stay with the use of traditional soy-containing
foods such as tofu, miso, tempeh and others, which have been
used traditionally in the Asian diet, versus too many
extracts of soy protein and soy protein isolates, which may
leave out some synergistic factors in soy that are of
benefit.
BONE
LOSS, MENOPAUSE AND VITAMIN C
In
evaluating 277 women (mean age of 71.8 years, 25.5 years
since menopause) who were regular vitamin C supplement users
out of a cohort of 994 community-based women (mean age of
72.9 years. 26.2 years since menopause), the daily vitamin C
supplement intake ranged from 00 to 5,000 mg. with a mean
dose of 745 mg. The average duration of use of vitamin C was
12.4 years. Eighty-five percent of the subjects had taken
vitamin C supplements for more than 3 years. After adjusting
for variables, vitamin C users had bone mineral density
levels approximately 3% higher at the midshaft radius,
femoral neck and total hip. After adjusting for further
variables, there was a significant difference remaining at
the femoral neck and marginal significant difference seen at
the total hip in those who took vitamin C versus those who
didn’t. In women currently taking both estrogen and
vitamin C, there was higher bone mineral density levels at
all sites, with marginal significance at the midshtaft
radius, femoral neck and total hip. Women who took vitamin C
plus calcium and estrogen had the highest bone mineral
density at the femoral neck, total hip, ultradistal radius
and lumbar spine.
“Vitamin
C Supplement Use and Bone Mineral Density in Postmenopausal
Women,” Morton Di, Barrett-Connor EL, Schneider DL, J Bone
Miner Res, 2001;16(1):135-140. (Address: Elizabeth
Barrett-Connor, MD, Dept Family Prey Med, Div Epidemiol,
Univ Calif San Diego, 9500 Gilman Dr, La Jolla, CA
92093-0607,U.S.A.) 37064
PEARL:
I think this is an excellent article with a lot of thought
behind it. There seems to be little harm in taking 500-1,000
mg of vitamin C per day, and so it gives me more reassurance
that my normal recommendations of 2,000-4,000 mg/day are not
going to hurt post-menopause bone mineral density, and
probably help.
Also,
vitamin C appears to work synergistically with calcium and
estrogen to maintain bone mineral density. These are pretty
simple measures to help reduce the risk of a very serious
condition.
Vitamin
C, calcium and exercise are fairly cheap bone loss
prevention
tools. Estrogen replacement may or may not be cheap,
depending on if one has it compounded and pays for it
out-of-pocket or uses the traditional medicines Premarin and
medroxyprogesterone. It is to be noted that the individuals
in this study were a little over 70 years of age and were
taking between 100 and 5,000 mg of vitamin C per day in
supplements.
CORONARY
ARTERY/HEART DISEASE, CHOLESTEROL, LIPID AND NUT
The
Dietary Approaches to Stop Hypertension (DASH) diet
recommends regular consumption of nuts, seeds and dried
beans at approximately 4 to 5 servings per week to help
control hypertension.
Most
of the fat in nuts is unsaturated, and they are the best
natural source of vitamin E. Nuts contain dietary fiber,
magnesium, potassium and arginine. which is the precursor of
nitric oxide. When almonds and walnuts are substituted for
traditional fats, there have been reductions of8- 1 2% in
LDL cholesterol. Four large cohort studies have shown that
eating nuts frequently is associated with a 30-50% reduced
risk of (coronary heart disease. Possible mechanisms include
LDL cholesterol reduction, the antioxidant actions of
vitamin E, and the effects of nitric 7
oxide on the endothelium and platelet function.
“Nut
Consumption, Lipids, and Risk of a Coronary Event,” Fraser
GE, Asia Pacific J C/in [‘lair, 2000;9(Suppl.):S28-S32.
(Address: Dr. Gary E. Fraser, Center for Health Res, Sc/tool
of Public Health. NH2008,Lon,a Linda Unip, Loma Linda, CA
92350, U.S.A., 1(909) 558-4753 /(FAX) 1 (909) 558-0126,
E-mail: gfrasei~asph./lu.edu) 37041
PEARL:
Because I am a vegetarian, a large part of my diet includes
raw nuts and seeds. I have never understood the low-fat
hypothesis taken to the extreme by excluding nuts. I have
never seen one study that shows that nut consumption
increases the risk of vascular disease. As this article
eloquently states, nuts are a great natural source of
vitamin E and cardioprotective nutrients, such as fiber,
magnesium, potassium and arginine. So much publicity has
been given to nitric oxide and its positive effect on
endothelial function. and nuts are rich in arginine, which
is the precursor of nitric oxide. As long as one does not
actually gain too much weight, since fat has 9 calories per
gram, then nut consumption should be encouraged in the
cardioprotective diet.
CORONARY
ARTERY/HEART DISEASE, DOCOSAHEXAENOIC ACID (DHA),
DOCOSAPENTAENOIC ACID (DPA), FISH OIL AND MERCURY
In
evaluating 1,871 men from the Kuopio Ischaemic Heart Disease
Risk Factor Study who were between 42 and 60 years of age
and had no evidence of coronary heart disease upon baseline
examination, a total of 194 patients had a fatal or nonfatal
acute coronary event during the follow-up period. Men who
were in the highest fifth of the proportion of serum DHA
plus DPA had a 44% reduction in risk of acute coronary
events compared with men in the lowest fifth. Men who were
in the highest fifth of serum DHA plus DPA levels who had a
low hair content of mercury (_2.0 mcg/g) had a 67°/o
reduced risk of acute coronary events compared with those in
the lowest fifth of DHA plus DPA who had a high hair content
of mercury (>2.0 mcg/g). Serum eicosapentaenoic acid
levels showed no association with risk of acute coronary
events. Studies examining high-fish intake and coronary
heart disease are inconsistent. The protective effect has
only been found for fatty fish. Cardiovascular disease is
common in Finland, especially in men, even though there is a
high fish intake. The mercury content in Finnish lakes is
high and high levels have been found in fish from these
lakes. It has been shown that a high intake of mercury from
non-fatty freshwater fish and the subsequent accumulation of
mercury in the body has been associated with an excess risk
of myocardial infarction in men in eastern Finland. Mercury
compounds might promote the peroxidation of DHA and DPA,
which are unsaturated fatty acids. Mercury also forms an
insoluble complex with selenium, preventing selenium from
acting as a cofactor for glutathione peroxidase. Mercury
might inhibit antioxidative mechanisms in humans. Fish is
the major source ofmethyl mercury in food. DPA may have a
cardioprotective effect.
“Fish
Oil-Derived Fatly Acids, Docosahexaenoic Acid and
Docosapentaenoic Acid, and the Risk of A cute Coronary
Events: The Kuopio ischaemic Heart Disease Risk Factor
Study,” Rissanen T, Voutilainen S, Nyyssonen K, et a!,
Circulation, November 28, 2000; 102:2677-2679. (Address: J.
7’. Salonen, Res !nsl Public Health, Univ Kuopio, P.O. Box
1627, 70211 Kuopic, Finland, E-mail: jukka.salonen@uku.fi)
37010
PEARL:
This is a very interesting article and brings up a
variety of issues. While fish consumption has been promoted
as a means of reducing heart disease and, in general, that
appears to be the case, due to pollution ofour waters,
mercury accumulation may alter our antioxidant balance and
negate some of the benefit of fish consumption. The
pollution factor, along with the fact that our fish
resources are being depleted worldwide, makes it imperative
that we try to consume more plant protein and products, as
well as find sources for these fatty acids in the vegetable
kingdom. These authors are to be commended for doing a
screening hair analysis to evaluate high mercury content,
and for investigating its relation to fatty acid levels.
This took some awareness and foresight.
MORTALITY
AND VITAMIN C
In
a prospective 4-year study evaluating plasma vitamin C
concentrations and al I-’cause mortality, cardiovascular
disease, ischemic heart disease and cancer in I 9,496 men
and women who were between 45 and 79 years of age, it was
found that plasma vitamin C concentrations were inversely
associated with mortality from all causes, and from
cardiovascular disease and ischemic heart disease in men and
women. The risk of mortality in the top vitamin C quintile
was about half the risk in the lowest quintile. A 20-umol/I
rise in plasma ascorbic acid concentration (equivalent to
about a 5O-g/day increase in fruit and vegetable intake) was
associated with an approximate 20% reduction in risk of
all-cause mortality. Plasma vitamin C was inversely related
to cancer mortality in men but not women. Increasing
vegetable and fruit intake by about I serving per day may
result in a reduction in the risk of all-cause mortality.
The inverse relationship between plasma vitamin C and
atherosclerosis and mortality may be due to individuals
taking supplements, which may include vitamin C or other
nutrients (such as fish oil), or it may indicate an
increased intake of fruits and vegetables. There is an
absence of effect on mortality in the trials of vitamin C
supplementation so far.
“Relation
Between Plasma Ascorbic Acid and Mortality in Men and Women
in EPIC-Norfolk Prospective Study: A Prospective Population
Study,” Khaw K-T’, Bingham: S, Welch A, et al, Lancet,
March 3, 2001;357:657-663. (Address: Prof Kay-Tee KhaH’,
Cliii Geroniol Unit, Box 251, Univ Cambridge School of Clin
Mcd, Addenbrooke’s Hosp, Cambridge, ~B2 2QQ, United
Kingdom, Email: kk 101@ntedschLcaim.ac. uk) 3706!
PEARL:
This is an important article and suggests to me, as a health
professional, that I keep encouraging myself and my patients
to
consume lots of fruits and vegetables. Vitamin C
supplementation is an insurance policy that may or may not
prove itself with regard to reducing mortality or
cardiovascular disease. But in my own experience, I feel
better and the risk is minimal, so why not take a few
thousand mg per day. The question is, “Are increased
levels of vitamin C a marker for a healthy lifestyle? Or is
the vitamin C itself the protective substance?” Without a
doubt, fruit and vegetable consumption is important, and
what is exciting about this work is that a small amount of
fruit and vegetable consumption, about I serving per day,
may reduce all-cause mortality by about 20%!
OBESITY
AND SUGAR
In
studying 548 ethnically diverse schoolchildren (mean age of
11 .7 years) from public schools who were studied
prospectively for 19 months, it was found that for each
additional serving of a sugar-sweetened drink, the body mass
index and frequency of obesity increased. Baseline
consumption of sugar-sweetened drinks was independently
associated with a change in body mass index. Excessive
bodyweight in children is the most common pediatric problem
in the United States. One of the contributing factors is the
consumption of sugar-sweetened drinks. The odds ratio of
becoming obese among children increases 1 .6 times for each
additional can or glass of sugar-sweetened drink that they
consume daily. Per capita, soft drink consumption has
increased almost 500% over the last 50 years. Half of all
Americans and 65% of girls and 74% of boys consume soft
drinks daily, most of which are sugar-sweetened. Soft drinks
are the leading source of added sugars in the diet,
accounting for 36.2 g daily for ~ adolescent girls and 57.7
g for boys. The increased consumption of soft drinks
coincides with secular increases in obesity that are
prevalent in children.
“Relation
Between Consumption of Sugar-Sweetened Drinks and Childhood
Obesity: A Prospective, Observational Analysis,” Ludwig
OS, Peterson KE, GortmakerSL, Lancet, February! 7,200
J;357:505-508. (Address:
Dr. 0. S. Ludwig, E-mail: david.ludwig~tch. harvard.edu)
37012
PEARL:
Personally, if and when I am going to have a soft drink, I
would rather have one that has sugar in it than one that has
an artificial sweetener. Artificial sweeteners give me
headaches. Secondly, I could see how, ifone was not aware of
the consequences,
it would be easy to ingest sugar-sweetened soft drinks. What
is not shared information is that sugar-sweetened soft
drinks are the way that caffeine is introduced into the
adolescent population, and caffeine is without a doubt
addictive. The combination of caffeine and sugar and its
effect on glycemic control, and the availability of refined
carbohydrates that can be consumed in sedentary adolescents
are really a prescription for obesity, fatigue and chronic
disease. This triad of caffeine, sugar-laden drinks and
refined-carbohydrate consumption is very prevalent and is
really a syndrome in-and-of itself (which 1 think wreaks
havoc with the health of a large segment of the busy
metropolitan and suburban population in the West). You add
to this equation television and the sedentary lifestyle that
goes with viewing it, as well as the positive reinforcement
for sugar-laden foods and soft drinks on TV, and one would
almost think it. is a conspiracy to get people hooked on
caffeine, sugar and refined and packaged foods. When one
spends as much time as I do taking dietary histories and
seeing the same dietary patterns over and over again related
to chronic complaints. it becomes obvious that addiction to
sugar-caffeine laden soft drinks is a public health issue.
PROSTATE
CANCER, SELENIUM AND VITAMIN E
In
evaluating 10.456 males from Washington County (mean age of
63 years at baseline), a total of 117 Out of 145 men who
developed prostate cancer and 223 matched controls had
toenail and plasma samples available. The risk of prostate
cancer declined with increasing concentrations of alpha-tocopherol.
For gamma-tocopherol. men in the highest fifth of the
distribution had a 5-fold reduction in risk of developing
prostate cancer compared with those in the lowest fifth. In
subjects who were in the top four-fifths of the distribution
of selenium. the association between selenium and prostate
cancer was in a protective direction compared with those in
the bottom fifth. There were statistically significant
protective associations for high levels of selenium and
alpha-tocopherol when gamma-tocopherol concentrations were
high. The authors recommend that both gamma- and alpha.
tocopherol supplements should be considered in prostate
prevention trials.
“Association
Between Alpha- Tocopherol, Gamma- Tocopherol, Selenium, and
Subsequent Prostate Cancer,” Helzlsouer KJ, Huang H-F,
A/berg AJ, et a!, J Nat! Cancer Inst, December 20,
2000;92(24):2018-2023. (Address: Kathy J. Helzlsouer, MD,
MHS. Dept Epidemiol, The Johns Hopkins Univ School of
Hygiene and Public Health, 615 N Wolfe 51, Baltimore, MD
21205, U.S.A., E-mail: Khelzlso@jhsph.edu) 37000
PEARL:
Because most studies are done with alpha-tocopherol,
it is difficult to really evaluate the other forms of
vitamin E, such as gamma-tocopherol. It has been stated that
the mixed tocopherols have more antioxidant activity, but
most of the time, the predominant portion of the vitamin E
supplement is alphatocopherol. Often the supplement will
say vitamin E with mixed tocopherols, which usually means a
very small amount of the mixed tocopherols is present. These
substances are very expensive compared with alpha-tocopherol,
so if there is an inexpensive vitamin E product and the
label states “with mixed tocopherols.” these substances
are probably present in very small amounts. Because gamma-tocopherol
is the main form found in the diet, it seems reasonable to
evaluate this form of vitamin E on its own. It is noted that
soybeans contain an 8:1 ratio of gamma-tocopherol to alpha-tocopherol.
In this study, higher concentrations of plasma gamma-tocopherol
were associated with a statistically significant lower risk
of developing prostate cancer. Gamma-tocopherol has been
shown to be a better inhibitor in vitro of electrophilic
mutagens than alpha-tocopherol.
ASTHMA
AND FOOD
In
107 subjects with asthma who were between 20 and 50 years of
age, subjects underwent a total of 143 food ingestion
challenges. In a group of2 I patients with “positive or
highly suggestive food history”, 21 food challenges were
conducted. In another group of 86 subjects with ~unknown
food history”, 122 challenges with food resulting in a
positive skin-response were performed. Seventy-one percent
of the 21 patients with a “positive food history” had
bronchial reactions to the foods. Forty-five of the 86
patients with “unknown food history” developed 68
bronchial responses to the food ingestion challenge.
Twenty-three of the subjects had immediate reactions (within
2 hours), II had late reactions (between 4 and 24 hours), 34
had a combination of immediate and late reactions, 6 had
delayed reactions (from 28-56 hours), and 9 had a
combination of immediate and delayed bronchial-obstructed
responses. The underlying immunologic and pathogenetic
mechanisms for these various food reactions are not known.
The authors conclude that the involvement of foods in
bronchial asthma is more prevalent than previously
expected.. There was no other correlation of the individual
types of bronchial responses to food ingested with other in
vivo or in vitro diagnostic tests. The authors conclude that
the involvement of food in bronchial asthma is more frequent
than previously thought and that food ingestion challenge is
the superior method of evaluating foods’ involvement with
asthma.
“Bronchial
Response to the Food Ingestion Challenge,” Pelikan Z,
Pelikan-Filipek M, Ann A/7~~.gy, March 198 7;58:164-I 72.
37223
PEARL:
The really important thing about this study is not
that food can aggravate asthma, which I think that most
people who deal with asthma would agree with, but that the
reactions were not necessarily related to the classic
allergy response (IgE). There were a minority of asthmatic
subjects who had significantly delayed responses to foods up
to 56 hours. Delayed food sensitivity is not likely to be
correlated with skin testing. Yet, the fact of the matter is
these people still had adverse reactions to foods. While I
have no problems with having patients try the different
types of in vitro blood testing for food intolerance, the
bottom line is that they still have to reintroduce foods and
watch for symptoms.
ATOPIC
DERMATITIS, FOOD ADDITIVE, FOOD INTOLERANCE AND LEUKOTRIENE
Ten
non-atopic individuals, 9 individuals who had improved Costa
skin score and eosinophil cationic protein (ECP) levels
after a low-pseudoallergen diet for 6 weeks but did not show
a worsening of enzema after double-blind, placebo-controlled
food challenges using food additives, and a third group of9
patients who had improved Costa skin score and ECP serum
levels after following a low-pseudoallergen diet for 6 weeks
and reacted to food additives through the double-blind,
placebo-controlled food challenge with worsening of eczema
were evaluated. Results showed that in the nonatopic group,
there was no increase in sulfidoleukotriene release with the
food additive testing. In the second group, the
sulfidoleukotriene production was below the cutoff range
in all the patients using benzoate, metabisulfite and
salicylate. In the third group, the sulfidoleukotriene
production was seen with food color mix in I out of 9
subjects, with tartrazine in 3 out of 9 subjects, with
benzoate in 4 out of 9 subjects, with nitrite in 5 Out of9
subjects, with salicylate in 2 out of9 subjects, and with
metabisulfite in I out of 9 subjects. There was no increase
in sulfidoleukotriene concentrations in the presence of
tested food additives in 2 patients in the third group.
Increased sulfidoleukotriene production by peripheral
lymphocytes was observed in the majority of patients with
proven food intolerance toward food additives in the
presence of single food additives. This occurred
particularly with the food additives tartrazine, benzoate
and nitrite. Single food additives may aggravate atopic
dermatitis through increased sulfidoleukotriene production.
“Increased
Leukotriene Production by Food Additives in Patients With
Atopic Dermatitis and Proven Food Intolerance,” Worm M,
Vieth W, Ehlers I, et al, Cllin, Exp Allergy,
2001;31:265-273. (Address: Margitta Worm,, KIinik fur
Dermatologie, Venerologie und Allergologie mitI
Asthmapoliklinik, Charite Campus-Mitte, Schuniannstr. 20-21,
D-101I 7 Berlin, Germanv, E-mail: margitta.worm@charite.de)
37189B
PEARL:
This is a unique study, because it has always been hotly
debated whether food additives have any true adverse
reactions. This makes it quite clear and attempts to give a
biochemical explanation, through the production of
leukotrienes by food additives that may be the aggravating
factors in atopic dermatitis. Essential fatty acid
supplementation of the omega-3 family, in particular, and
the elongated omega-6 family, such as gammalinolenic acid
and dihomo-gamma-linolenic acid, can result in prostaglandin
formation that may help displace arachidonic acid, thereby
reducing the production of leukotrienes.
CANCER
AND VEGETABLE CONSUMPTION
In
over 200 epidemiologic studies regarding vegetable and fruit
intake. it was found that a majority show an inverse
relationship between I or more vegetable and/or fruit
categories of intake at every cancer site, except prostate.
The data strongly suggest a wide variety of plant foods and
not just I or 2 varieties reduce the risk of cancer. Legumes
and potatoes appear to have no direct benefit on cancer risk
reduction. In 20 cohort studies, vegetable and fruit
consumption has been shown to have an inverse association
with cancer. Lung cancer had the most consistent evidence,
with regard to an inverse association between vegetable
and/or fruit consumption. Most of the human evidence for an
inverse association with vegetable and fruit consumption
came from case control studies. A statistically
significant inverse association has been• noted for I or
more vegetable and/or fruit categories in more than 70% of
the studies for cancers of the stomach, esophagus, lung,
oral cavity and pharynx, endometrium, pancreas, colon and
skin. Prostate cancer is the only cancer for which the
majority of studies have not noted at least statistically
significant adverse association. Anticarcinogenic substances
found in plant food include carotenoids, ascorbate,
tocopherols, selenium, dietary fiber, dithiolthiones,
isothiocyanates, indoles, phenols, protease inhibitors,
allium compounds, plant sterols, limonene and others. DNA
damage has to occur several times before a cell becomes
fully cancerous. At almost every stage of the cancer
process, phytochemicals can alter the likelihood of
manifesting the cancer. The World Cancer Research Fund
suggests eating 400-800 g/day or 5 or more portions per day
of a variety of vegetables and fruit year round, and this
may lead to a 30-40% reduction in world cancer incidence.
Nutritional supplements do not provide the diversity of
components that are found in food and do not provide the
same taste and enjoyment as plant food.
“Your
Mother Was Rig/it: Eat Your Vegetables,” Potter JD, Asia
Pacific J Clin Nutr, 2000; 9(Suppl.):S10-S12. (Address: Prof
J. D. Potter, E-mail: jpotte@flicrc.org) 371 93B
PEARL:
With the focus on the protein diets, I think that
individuals and health professionals are making a serious
mistake in not highlighting vegetables and fruits as the
most important thing we can do, with regard to diet. Some of
the benefit of meat consumption comes from the high nutrient
density of those foods. Another benefit comes from
controlling blood sugar by avoiding refined carbohydrates
and common allergens. But the short-term benefit of the
protein-rich diets, especially those rich in animal
products, may not provide long-term benefit, of which there
is overwhelming evidence for vegetable and fruit
consumption.
CARDIOVASCULAR
DISEASE, DIET AND ENDOTHELIAL
FUNCTION
Evidence
suggests that omega-3 fatty acids, antioxidant vitamins (in
particular vitamins E and C), folic acid and L-arginine have
beneficial effects on endothelial function. The mechanism of
action may be by either decreasing endothelial activation or
by improving endothelium dependent vasodilation in
individuals who are at high risk for cardiovascular disease
as well as in healthy individuals. Dose ranges for omega-3
fatty acids between 4 and 5.1 g/day and lasting from 3 weeks
to 4 months have been shown to be of benefit. There also
needs to be a concomitant reduction in omega-6 fatty acids
to increase the likelihood of improvement in endothelial
function. Dose ranges of vitamin E between 300 and 1,000 IU
per day and vitamin C between 500 mg and 2 g/day
individually have shown benefit in endothelial function. For
folic acid, the dose range is between 5 and 10 mg/day,
lasting from 2 to 12 weeks. Doses of L-arginine between 8
and 21 g have shown improvement in endothelial function.
“Dietary
Modulation of Endothelial Function: Implications for
Cardiovascular Disease,” Brown AA, Hu FR, Am J Clin Nutr,
2001;73:673-686. (Address: F. B. Hu, Dept. Nutr, Harvard
School of Public Health, 665 Huntington Aye, Boston, MA
02115, U.S.A., Email: frank.hu~channing.harvard.edu) 37208
PEARL:
This is an excellent article and provides us with a
group of nutrients that, at moderate doses, except for
possibly L-arginine, may be practical for the ambulatory
patient with cardiovascular disease. The dose ranges of
500-2,000 mg of vitamin C, 300-1,000 IU of vitamin E, 1 mg
of folic acid and possibly lower doses of L-arginine at 2
g, in combination, may have a synergistic effect, but that
needs to be proven. Because these agents are of low risk,
except possibly for people who have herpes (L-arginine can
stimulate herpes), they appear to be reasonable adjuncts to
the cardiovascular disease patient’s medication and
lifestyle treatments.
CARDIOVASCULAR
DISEASE, HOMOCYSTEINE, OMEGA-3 FATTY ACID, VEGETARIAN AND
VITAMIN B12
In
13 women and 5 men who were 38 years of age and were
vegetarians, with a body mass index of 22.6, I week after a
single intramuscular injection of cyanocobalamin at 10,000
meg, results showed an increase in serum vitamin B 12 levels
from 149 to 532 pg/mI and a total homocysteine level that
dropped from 12.4 to 7.9 umol/l. In 10 out of 14 of these
same vegetarians who completed an 8-week supplementation
trial with 700 mg/day each of eicosapentaenoic acid and
docosahexaenoic acid, there was an increase in these fatty
acids being incorporated in plasma lipids and there was a
reduction in platelet aggregation to agonists. From a single
injection of cyanocobalamin in vegetarians, there was
normalization of vitamin Bl2 and a 36% reduction in fasting
total homocysteine levels.
“Cardiovascular
Risk Factors in Vegetarians: Normalization of
Hyperhomocysteinemia With Vitamin B12 and Reduction of
Platelet Aggregation With n-3 Fatty Acids,” Mezzano D,
Kosiel K, Martinez
C, et al, Thromb Res, 2000;100:153-160. (Address: Diego
Mezzano, (FAX) +56 (2) 686 3772, E-mail: dmezzano@med.puc.cl)
37180
PEARL:
Two interesting components to this article come to
mind. The first is the authors’ use 10,000 mcg of vitamin
B12 in a single shot. That is generally 10 cc of vitamin
B12. This group does not report any side effects from this
dosage. Secondly, this vitamin BI 2 injection drove down
homocysteine levels, although there were normal folic acid
levels before and after the injection. Serum pyridoxal
phosphate levels were also within the normal range in this
study. So the question arises, if we gave 500 mcg of vitamin
B12, which is a large dose, would we drive down homocvsteine
levels? Or, do we need supraphysiological doses of vitamin
B12, such as 10,000 mcg, to somehow push the remethylation
pathway to convert homocysteine to methionine and lower the
risk of vascular disease while lowering total homocysteine
levels? This is a very interesting question.
CHOLESTEROL,
POLYUNSATURATED FATTY ACID (PUFA) AND VEGETABLE CONSUMPTION
Thirty-one
hypercholesterolemic subjects (20 males and II females. mean
age of 39.7 years and 50.0 years, respectively) consumed for
3 weeks two l60-g cans/day of a green vegetable juice. which
contained the juice from broccoli, cabbage, Japanese radish
leaves, celery,
spinach, lettuce and parsley and was sweetened with
apple and lemon juices. Results showed an increase in
erythrocyte membrane phospholipid PUFAs and reduced
saturated fatty acid levels. The polyunsaturated fatty
acid/saturated fatty acid ratio was increased significantly
from 0.26 to 0.49. Green vegetable juice consumption
increased both omega-6 and omega-3 PUFAs, but the increase
in omega-3 PUFAs was greater than that ofomega-6 PUFAs. This
resulted in a reduction ofthe omega-6/omega-3 fatty acid
ratio from 4.29 to 3.00. Plasma thiobarbituric acid reactive
substances were reduced following green vegetable juice
consumption.
“Green
Vegetable Juice Increases Polyunsaturated Fatty Acid of
Erythrocyte Membrane Phospholipid in Clin Nutr, 2000;9@fhw.oka-pu.ac.jp)
37170
PEARL:
This is a very enjoyable article for me to read,
because it so clearly shows that the concentrated
consumption of vegetables does virtually everything right to
improve our health and prevent chronic diseases. The popular
belief is that vegetables are rich in phytochemicals that
may have antioxidant properties and are beneficial for us.
What may not be common knowledge is that these vegetables
may also contain fatty acids in the appropriate ratios which
may reduce our risk of inflammatory disease. I was quite
surprised to see that there was an increase in omega-3 fatty
acids compared with omega-6 fatty acids. Therefore, just
consuming vegetables, and not necessarily having to consume
fish or sea vegetables, can improve our fatty acid ratio and
reduce our risk of vascular disease, as well as other
inflammatory conditions.
CHRONIC
DISEASE, DIET AND LIFESTYLE
It
is noted that hunter gatherer lifestyles, in general, are
free from degenerative disorders. This occurred whether the
diets were high in fat, supplying 28-58% of the energy, as
noted in some studies, or lower in fat, as in agricultural
hunter-gatherer populations. In current traditional pastoral
societies in Africa where diets have been typically 15-20%
fat, there is a low incidence of heart disease, diabetes and
obesity. In rural areas in Africa, coronary heart disease is
still virtually absent. Elderly Africans living their
traditional lifestyle still die almost entirely from
infection arid not chronic disease. Left out of the diet
equation is the significant amount of daily physical
activity by these individuals and the low levels of smoking.
In reviewing Massachusetts 9eneral Hospital wards between
1910 and 1920, coronary heart disease was rare. Americans
were poor at this time. Currently in Spain, the population
has approximately one-fifth the coronary heart disease as in
Poland. In the United States, the death rate from coronary
heart disease in New Mexico is approximately half of that in
New York. Despite the ~frequency of death from degenerative
diseases, the expected lifetime is approximately 75 years of
age for men and 80 years for women. It has been estimated
that if the present rate of obesity in the United States
continues, all Americans will be obese by the year 2230.
Health educators have a difficult time getting their peers
and themselves to participate in healthy lifestyles, which
include eating significant amounts of fruits and vegetables
daily. The author concludes by stating “in brief, no
matter what efficacious lifestyle changes are recommended,
whether they be derived from past or from present
experiences of populations, they seem almost irrelevant
because they will be very largely ignored.”
“Are
Health and Ill-Health Lessons Front Hunter-Gatherers
Currently Relevant?” Walke’r ARP, An: J C/in Nutr,
2001;73:353-354. (Address: Dr. Alexander R. P. Walker, E-mail:alex@mail.saimr.wits.ac.za)
37171
PEARL:
When I read this editorial, two things come to mind.
One is that almost no matter what types of foods we eat,
they have to be in their most unrefined state in order to
reduce the risk of degenerative disease. Second, the human
organism is meant to be mobile and very physically active.
No amount of dietary supplements or diet can overcome that
fact. Even when one tells a patient to exercise 3 or 4 days
a week for a half hour a day, which might be significant for
the general population, that in no way equates to how we
evolved, which was moving for hours every day doing vigorous
activity. The goal really should be some type of exercise
every single day of one’s life. It is quite an amazing
prediction, that if the present rate of obesity increases,
all Americans will be obese by the year 2230.
CORONARY
ARTERV/HEART DISEASE, CHOLESTEROL, FAT AND NUT
CONSUMPTION
Almost
80% of the energy that is found in nuts comes from fat,
although the majority is in the form of monounsaturated
fatty acids or polyunsaturated fatty acids. Nuts also
contain dietary fiber, potassium, magnesium and copper. The
best natural source of vitamin E comes from nuts. Nuts are
also rich in arginine, which stimulates nitric oxide, a
potent vasodilator. Human feeding trials with almonds and
walnuts being substituted for traditional fat led to an
8-12% reduction in LDL cholesterol. Macadamia nuts and
hazelnuts may also be of benefit. It is unlikely that modest
daily consumption of nuts leads to obesity. Most studies
have shown that eating nuts frequently reduces the risk of
coronary heart disease by 30-50%. Possible mechanisms by
which nuts ma~ be cardioprotective include reductions in LDL
cholesterol. the antioxidant actions of vitamin E, and the
effects on the endothelium and platelet function due to
higher levels of nitric oxide derived from arginine in nuts.
“Nut
Consumption, Lipids, and Risk of a Coronary Event,” Fraser
GE, Asia Pacific J C/in N~, 2000; 9(Suppl.):S28-S32.
(Address: Dr. Gary E. Fraser, E-mail: gfraser@sph.llu.edu)
37213
PEARL:
I have never seen a study that shows an adverse
consequence of eating raw nuts or seeds, or for that matter
an~ type of nuts or seeds, with regard to cardiovascular
disease and general health. It is always stated that they
are so fattening, but I have yet to see someone who is a raw
nut and seed eater be significantly ‘
overweight, One key component of nuts and seeds,
aside from their fiber, magnesium, copper, protein and
essential fatly acids content, is that nuts are one of the
best sources of vitamin E. The~ also contain arginine, which
stimulates nitric oxide a potent vasodilator.
OBESITY,
CHILDREN, PHYSICAL ACTIVITY AND TEENAGER
In
the March 9,2001 issue of Morbidity and Mortality Weekly
Report. it was stated that regarding physical activity rates
over the I 990s. the number of individuals who achieved 30
minutes of moderate activity. 5 times a week, or 20 minutes
or vigorous activity, 3 times a week. changed little, from
24.3% of the population in 1990 to 25.4°/o of the
population in 1998. Among children aged 6 to II years. those
who were considered overweight increased from II % in 1994
to 13% in 1999. In 1976, 7% ofthe children were overweight.
In those teenagers who were between 12 and 19 years of age,
compared to those who were overweight in 1994, there was a
30% increase in 1999, from II % to 14%, respectively. In
1976, only 5% of teens were overweight.
“Obesity,
Children and Physical Activity,” Nutrition Week, March 16,
2001;31(1 1): 7/Morbidity and Mortality Weekly Report, March
9, 2001;50:166-169/Centers for Disease Control and
Prevention press release, March 12, 2001. 37138
PEARL:
I could go on and on about the benefits of exercise
for this country as a whole, and for our specific population
of patients. Everyone knows the importance of exercise, but
unless we emphasize it every time we see patients, they
probably won’t understand how important it is to their
health and “pocket book.” I think if we questioned
patients on every visit regarding their current exercise
program, or lack thereof, we would also be reminding
ourselves of just how important exercise is to any treatment
protocol. This consistent reminder of the value of exercise
would help people get well faster and at a lower cost.
Children becoming obese is directly related to their
physical inactivity, television watching or video games, and
the consumption of refined carbohydrates.
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