Re: The definitive study on dietary fat and weight

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Some relative citations from the Harvard nurses' study, and others:

>>>Several studies have shown that high-carbohydrate low-fat diets lead
to high triglycerides, elevated serum insulin levels, lower HDL
cholesterol levels, and other factors known to raise the risk of
coronary artery disease. (See Liu GC; Coulston AM; Reaven GM. Effect
of high-carbohydrate low-fat diets on plasma glucose, insulin and
lipid responses in hypertriglyceridemic humans. Metabolism, 1983 Aug,
32:8, 750-3. *

*See also Coulston AM; Liu GC; Reaven GM. Plasma glucose,
insulin and lipid responses to high-carbohydrate low-fat diets in
normal humans. Metabolism, 1983 Jan, 32:1, 52-6. See also Olefsky JM;
Crapo P; Reaven GM. Postprandial plasma triglyceride and cholesterol
responses to a low-fat meal. American Journal of Clinical Nutrition,
1976 May, 29:5, 535-9. See also Ginsberg H et. al. Induction of
hypertriglyceridemia by a low-fat diet. Journal of Clin Endocrinol
Metab, 1976 Apr, 42:4, 729-35) *

*High intake of fats from the Omega-3 group increase HDL cholesterol,
which is considered protective against heart disease. Obviously it
would be difficult to eat an Omega-3 rich diet while following a
traditional fat reduced diet, especially if one were following one of
the popular American diets that has one eating only 20-30 grams of fat
per day. (Franceschini G. et. al. Omega-3 fatty acids selectively
raise high-density lipoprotein 2 levels in healthy volunteers.
Metabolism, 1991 Dec, 40:12, 1283-6. See also Journal of the American
College of Nutrition 1991:10(6);593-601) *

***********A recent American study showed that low-fat, high-carbohydrate diets
(15% protein, 60% carbohydrate, 25% fat) increase risk of heart
disease in *post-menopausal women* over a higher fat, lower carbohydrate
diet (15% protein, 40% carbohydrate, 45% fat). (Jeppeson, J., et. al.
Effects of low-fat, high-carbohydrate diets on risk factors for
ischemic heart disease in postmenopausal women. American Journal of
Clinical Nutrition, 1997;65:1027-33) **

*The largest and most comprehensive study on diet and breast cancer to
date, studying over 5,000 women between 1991 and 1994, showed that
women with the lowest intake of dietary fat had a significantly higher
incidence of breast cancer than the women with the highest intake of
dietary fat. It also found that women with the highest intake of
starch had a significantly higher incidence of breast cancer than the
women with the lowest intake of starch. The study found no evidence
that saturated fat had any effect one way or the other on breast
cancer, and that unsaturated fat had a significantly protective effect
against breast cancer. (Franceschi S et. al. Intake of macronutrients
and risk of breast cancer. Lancet; 347(9012):1351-6 1996)*

*The commonly-held belief that the best diet for prevention of
coronary heart disease is a low saturated fat, low cholesterol diet is
not supported by the available evidence from clinical trials. In
primary preventions, such diets do not reduce the risk of myocardial
infarction or coronary or all-cause mortality. Cost-benefit analyses
of extensive primary prevention programmes, which are at present
vigorously supported by governments, health departments, and health
educationalists, are urgently required....Similarly, diets focused
exclusively on reduction of saturated fats and cholesterol are
relatively ineffective for secondary prevention and should be
abandoned. There may be other effective diets for secondary prevention
of coronary heart disease but these are not yet sufficiently well
defined or adequately tested." (European Heart Journal, Volume 18,
January 1997.)*

*We found no evidence of a positive association between total dietary
fat intake and the risk of breast cancer. There was no reduction in
risk even among women whose energy intake from fat was less than 20
percent of total energy intake. In the context of the Western
lifestyle, lowering the total intake of fat in midlife is unlikely to
reduce the risk of breast cancer substantially." (Hunter, DJ et. al.
Cohort studies of fat intake and the risk of breast cancer - A pooled
analysis. New England Journal of Medicine, 334: (6) FEB 8 1996)*


2) Title: DG-DISPATCH - ENDO 99: Diabetics Improve Health With Very
High-Fat,
Low
Carb Diet
Doctor's Guide
June 15, 1999

By Cameron Johnston
Special to DG News

SAN DIEGO, CA -- June 15, 1999 -- A very high-fat, low-carbohydrate diet
has
been shown to have astounding effects in helping type 2 diabetics lose
weight
and improve their blood lipid profiles.

The results of three studies involving such a diet, which is similar to,
but
has a few key differences from the famous "Dr. Atkins Diet", were
presented
today
at the annual meeting of the Endocrine Society.

Dr. James Hays, an endocrinologist and director of the Limestone Medical
Center in Wilmington, DE, admitted that the concept of a high-fat diet in
people
who are already at higher risk of cardiovascular disease might seem
incongruous.
Nonetheless, this study of 157 men and women with type 2 diabetes showed
an
impressive benefit in body mass index (BMI) triglycerides, HDL, LDL and
HbA1c.


Most people are encouraged to reduce the amount of fat in their diets,
particularly saturated fats, and diabetics in particular are advised to
reduce
their
overall caloric intake, Dr. Hays explained in an interview in San Diego
during
the
conference.

Whereas a normal diet would be in the order of 1800 to 2100 calories,
with 60
percent of calories coming from carbohydrates and 30 percent from fat,
patients

in this diet were restricted to 1800 calories per day and were
encouraged to
get
50 percent of their caloric intake from fat, and just 20 percent from
carbohydrates.
The balance of 30 percent would come from proteins.

A whopping 90 percent of the fat content in their diets was saturated
fat,
compared
with just 10 percent that was monounsaturated fat.

"I think this is at least worth considering for any diabetic," Dr. Hays
said in
an interview.
"The thing many diabetics coming into the office don't realize is that
other
forms of
carbohydrates will increase their sugars, too. Dietitians will point them
toward complex carbohydrates ... oatmeal and whole wheat bread, but we
have to
deliver the message that these are carbohydrates that increase blood
sugars,
too."

Higher-fat diets, on the other hand, seem to make the person feel full
faster
so they eat less; higher-fat diets also tend to reduce postprandial
hypoglycemia so the patients feel better after eating.

"Every diabetic comes home from the doctor with instructions as to what
their
diet should consist of, but they're not getting the information from
dietitians about what complex carbohydrates they should eat,"

Dr. Hays said:
"The important thing here is no ketosis. We absolutely don't want people
to
become
ketotic, and so we said they had to have so many exchanges of fresh
fruits and
vegetables and we specified the ones they could eat."

They were able to eat all the meat and cheese they wanted, but as for
carbohydrates, they are restricted to eating unprocessed foods, mainly
fresh
fruit and vegetables, he added.

Subjects recruited into the study (84 men, 73 women) were all type 2
diabetics
and
were required to undergo a standard American Diabetes Association
modified diet
for
one full year before entry into the trial. Over the course of one year,
the
subjects achieved a mean decline in total cholesterol of between 231 and
190
mg/dl. Triglycerides declined from 229 to 182 mg/dl.

Low-density lipoproteins (LDL cholesterol) fell from 133 to 105 mg/dl,
while
HDL
increased from 44 to 47 mg/dl.

HbA1c, which at the start of the study averaged 3.34 percent above
normal,
declined to the point that at one year, the mean was just 0.96 percent
above
normal.

The average weight loss among subjects in the study was in the order of
40
pounds, Dr. Hays said.

By the end of the one-year study, he added, 90 percent of the patients
had
achieved ADA (American Diabetes Association) targets for HbA1c, HDL,
LDL and triglycerides.

Even among juvenile diabetics, he said, they might not be overweight and
they
might have more or less normal lipid levels, but when they are on this
kind of
diet
it is possible to treat them with lower doses of insulin and make their
lives a
little
safer, he said.

As for the response from cardiologists who see a high-fat diet as
anathema to
what they have been instructing their patients for years now, Dr. Hays
said he
has
three cardiologist patients who are now on the diet.

"If you have a diet that results in weight loss, lower cholesterol, and a
better lipid profile, eventually, everybody will be eating that way.
It's going
to come
whether we like it or not."

*********The New England Journal of Medicine -- November 20, 1997 -- Vol. 337,
No. 21


Dietary Fat Intake and the Risk of Coronary Heart Disease in Women
Frank B. Hu, Meir J. Stampfer, JoAnn E. Manson, Eric Rimm, Graham A.
Colditz, Bernard A. Rosner, Charles H. Hennekens, Walter C. Willett
-------------------------------------------------------------------------
-------

Abstract
Background. The relation between dietary intake of specific types of
fat, particularly trans unsaturated fat, and the risk of coronary
disease remains unclear. We
therefore studied this relation in women enrolled in the Nurses' Health
Study.

Methods. We prospectively studied 80,082 women who were 34 to 59 years
of age and had no known coronary disease, stroke, cancer,
hypercholesterolemia, or
diabetes in 1980. Information on diet was obtained at base line and
updated during follow-up by means of validated questionnaires. During 14
years of follow-up, we
documented 939 cases of nonfatal myocardial infarction or death from
coronary heart disease. Multivariate analyses included age, smoking
status, total energy intake,
dietary cholesterol intake, percentages of energy obtained from protein
and specific types of fat, and other risk factors.

*****Results. Each increase of 5 percent of energy intake from saturated fat,
as compared with equivalent energy intake from carbohydrates, was
associated with a 17
percent increase in the risk of coronary disease (relative risk, 1.17;
95 percent confidence interval, 0.97 to 1.41; P = 0.10).****** As compared
with equivalent energy from
carbohydrates, the relative risk for a 2 percent increment in energy
intake from trans unsaturated fat was 1.93 (95 percent confidence
interval, 1.43 to 2.61;
P<0.001); that for a 5 percent increment in energy from monounsaturated
fat was 0.81 (95 percent confidence interval, 0.65 to 1.00; P = 0.05);
and that for a 5
percent increment in energy from polyunsaturated fat was 0.62 (95
percent confidence interval, 0.46 to 0.85; P = 0.003). Total fat intake
was not significantly
related to the risk of coronary disease (for a 5 percent increase in
energy from fat, the relative risk was 1.02; 95 percent confidence
interval, 0.97 to 1.07; P = 0.55).
We estimated that the replacement of 5 percent of energy from saturated
fat with energy from unsaturated fats would reduce risk by 42 percent
(95 percent confidence
interval, 23 to 56; P<0.001) and that the replacement of 2 percent of
energy from trans fat with energy from unhydrogenated, unsaturated fats
would reduce risk by
53 percent (95 percent confidence interval, 34 to 67; P<0.001).

**Conclusions. Our findings suggest that replacing saturated and trans
unsaturated fats with unhydrogenated monounsaturated and polyunsaturated
fats is more effective
in preventing coronary heart disease in women than reducing overall fat
intake. (N Engl J Med 1997;337:1491-9.) **


Source Information
>From the Departments of Nutrition (F.B.H., M.J.S., E.R., W.C.W.),
Epidemiology (M.J.S., J.E.M., E.R., B.A.R., W.C.W.), and Biostatistics
(B.A.R.),
Harvard School of Public Health; and the Channing Laboratory (M.J.S.,
J.E.M., E.R., G.A.C., B.A.R., C.H.H., W.C.W.) and the Division of
Preventive
Medicine (J.E.M., C.H.H.), Department of Medicine, Brigham and Women's
Hospital and Harvard Medical School -- all in Boston. Address reprint
requests to Dr.
Hu at the Department of Nutrition, Harvard School of Public Health, 665
Huntington Ave., Boston, MA 02115.

Ann Intern Med 1998 Apr 1;128(7):524-33



Metabolic risk factors worsen continuously across the spectrum of
nondiabetic glucose tolerance. The Framingham Offspring Study.

Meigs JB, Nathan DM, Wilson PW, Cupples LA, Singer DE
Massachusetts General Hospital, Harvard Medical School, Boston
University School of Public Health, 02114, USA.
jmeigs@xxxxxxxxxxxxxxxxxxx

BACKGROUND: Categorical definitions for glucose intolerance imply that
risk thresholds exist, but metabolic risk for type 2 diabetes mellitus
or cardiovascular
disease may increase continuously as glucose intolerance increases.
OBJECTIVE: To examine the distributions of the following metabolic risk
factors across the
spectrum of glucose tolerance: overall and central obesity,
hypertension, low levels of high-density lipoprotein cholesterol, and
increased triglyceride and insulin
levels. DESIGN: Cross-sectional analysis. SETTING: The community-based
Framingham Offspring Study. PARTICIPANTS: 2583 adults without previously
diagnosed diabetes. MEASUREMENTS: Clinical data; fasting glucose,
insulin, and lipid levels; and glucose and insulin levels taken 2 hours
after oral challenge
were collected from 1991 to 1993. Glucose tolerance was determined by
1980 World Health Organization criteria. Patients with normal glucose
tolerance were
categorized into quintiles of fasting glucose. The distributions of each
metabolic risk factor and the metabolic sum of the six risk factors were
assessed across seven
categories from the lowest quintile of normal fasting glucose level
through impaired glucose tolerance and previously undiagnosed diabetes.
RESULTS: The mean
age of patients was 54 years (range, 26 to 82 years); 52.7% of patients
were women. Glucose tolerance testing found that 12.7% of patients had
impaired glucose
tolerance and 4.8% had previously undiagnosed diabetes.
Multivariable-adjusted mean measures of risk factors and odds ratios for
obesity, elevated waist-to-hip ratio,
hypertension, low levels of high-density lipoprotein cholesterol,
elevated triglyceride levels, and hyperinsulinemia showed continuous
increases across the spectrum
of nondiabetic glucose tolerance. Although a threshold effect near the
upper range of nondiabetic glucose tolerance could not be ruled out for
triglyceride levels in
men and for insulin levels 2 hours after oral challenge in men and
women, no other metabolic risk factors showed clear evidence of
thresholds for increased risk.
CONCLUSIONS: Metabolic risk factors for type 2 diabetes mellitus and for
cardiovascular disease worsen continuously across the spectrum of
glucose tolerance
categories, beginning in the lowest quintiles of normal fasting glucose
level.

PMID: 9518396, UI: 98175274

Susan
.

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