Dr. Lam Author of
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Academy of Anti-aging ResearchAn important study has revealed that a low fat
diet high in carbohydrates, fiber, legumes and low in red meat may not reduce
total cholesterol levels and lower the risks of cardiovascular disease (CVD) and
colon cancer. The health authorities are therefore advised to make appropriate
changes to nutritional recommendations and food labels
Schatzkin and co-authors at the National Cancer
Institute (NCI) compared two groups of similar subjects from 2000 men and women
aged at least 35 (average age is 61). One group ate their usual diets and the
other group ate a lower fat higher fiber diet.
The subjects were then randomly assigned to
either an “intervention” group or a “control group”. The intervention
group was given 50 hours of counseling sessions, which included nutritional
information, behavior modification techniques, and consultations with
nutritionists and dietary assessments. The group also ate a low fat (fat ~ 20
per cent of total calories), high fiber diet (18 g of dietary fiber per 1000
kcal or ~ 35 grams per day) which included fruits and vegetables (3.5 servings
per 1000 kcal or 5 to 8 servings daily).
The control group was given a brochure on healthy
eating with general dietary guidelines from the National Dairy Council but no
additional nutritional or behavioral information. They were assigned to follow
their usual diet.
The subjects were followed for about four years
after randomization. On average, there were no major differences between both
groups in weight change (the control group gained about 1lb), folate intake
(intervention group ate a little more and showed that folate did not have a big
effect), multivitamin use (about 40 per cent took them) or calcium intake (about
1000 mg per day).
The intervention group ate more fiber, less red
meat, less fat (about 35 per cent for the control group and 24 per cent for the
intervention group), fewer calories (little difference which was bout 1900 cal
per day for either group), more fruits and vegetables (from 2 to 3.4 servings
per day for the intervention group, 2 to 2.2 servings for control); more whole
grains (from 80 to 115 g per day for the intervention group and remained at
about 75 g per day for the control group), more legumes (15 g per day for the
intervention and about 15 g per day for the control).
According to the New England Journal of Medicine,
despite eating more vegetables, fruits and fiber, serum carotenoid levels and
total cholesterol were about the same as before and after the study for both the
experimental and control groups. Both groups have similar incidence of colon
cancer.
Subjects in both groups reported on an average
similar variables such as age, sex, minority status, education, marital status,
smoking (13 per cent does not distinguish heavy from light smokers), alcohol
intake (7 to 8 g per day, about ˝ ounce alcohol or about 5 ounces wine per day
on average), body mass index (about 27), vigorous or moderate activity or both
(about 12 hr per wk), aspirin use (20 per cent), use of calcium supplements
(about 15 per cent), use of vitamin E supplements (about 17 per cent), total
plasma cholesterol (about 200mg/dl), total serum carotenoids (about 90 ug/dl)
and serum alpha-tocopherol 9about 1400 ug/dl). However, key dietary variables
such as intake of essential fats were not measured in the groups or in the diet.
Information provided is courtesy of and compiled
by the Academy of Anti-aging Research staff, editors, and other reports.
Anti-Aging Perspective:
This is an important study published in one of
the most respected medical journals in America. Yes, its about time that America
wakes up to the sad reality that simply following a low fat diet high in fiber,
as that promoted by the medical community in the past 20 years, is unlikely to
lower abnormal lipids (cholesterol, triglycerides, etc) or prevent CVD.
Government dietary recommendations and many prepared foods ought to be changed
if the desired goal is to have a significant impact on CVD. The best strategy
for maintaining healthy lipids and preventing CVD is to eat natural foods rich
in essential fats, and eat few calories (only as much as needed to maintain
ideal weight). The Mediterranean diet comes closest to this. Avoiding fat is not
necessarily healthy, particularly if it means avoiding essential fats. However,
we should avoid highly processed fats such as margarine and refined
carbohydrates, as they release free radicals and leads to many harmful effects.
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