Do Saturated Fats and Trans Fats Cause Type-2 Diabetes?

[Guest guest]

Do Saturated Fats and Trans Fats Cause Type-2 Diabetes?

By _Mary G. Enig_

(http://www.westonaprice.org/knowyourfats/type-2-diabetes.html#author) , PhD

_http://www.westonaprice.org/knowyourfats/type-2-diabetes.html_

(http://www.westonaprice.org/knowyourfats/type-2-diabetes.html)

Question: I am having a very difficult time defending the benefits of a diet

rich in saturated fat. I attend Bastyr University, a naturopathic medical

school, and through all my nutriton classes, saturated fat has been deemed

unhealthy and detrimental to one's health. For instance, my Diet and Nutrient

Therapy class professor cites a 2002 article in the British Journal of

Nutrition, " Acute effects of a meal fatty acid composition on insulin

sensitivity in

healthy post-menopausal women " 1 as showing that saturated fat reduces insulin

sensitivity, thereby contributing to type-2 diabetes. He also cited a 2002

study in Diabetologia, " Substituting dietary saturated fat with polyunsaturated

fat changes abdominal fat distribution and improves insulin sensitivy. " 2 I

would be very interested in your comments on these studies and your views on

saturated fat and diabetes.

Answer: Insulin insensitivity has been postulated to be the underlying

factor for type-2 diabetes; that is, a condition in which the receptors for

insulin on the cell membranes do not work very well. In type-2 diabetes, the

pancreas secretes insulin, but since the receptors don't work, the bloodstream

contains chronic high levels of insulin and glucose, while little gets into the

cell where it is needed.

In the first study cited by your professor, four groups of subjects were fed

a breakfast of rice krispies, banana, skimmed milk, " Nesquik " (presumably a

chocolate drink) and something called " Marvel, " along with 40 grams of fat.

The first group got mostly saturated fat from palm oil, the second group got

mostly monounsaturated fat from olive oil, the third group got mostly omega-6

fatty acids from safflower oil and the fourth group got mostly omega-3 fatty

acids from a combination of safflower oil and fish oil.

Levels of insulin and glucose in the blood were measured at intervals after

breakfast and also after a so-called low-fat lunch consisting of cheese pizza

(said to contain only 5.4 grams of fat), lettuce, cucumber and tomatoes.

Those given the mostly saturated palm oil had higher insulin levels at about

one

hour after breakfast and lunch compared to the other three groups. However,

insulin levels were the same as the other groups two hours after each meal.

Blood glucose levels followed a similar curve for all four groups.

This is a very poor study to justify a recommendation against saturated fat.

All four groups were on a very unnatural diet high in processed foods, and

the fats used do not reflect the type of fatty acid profiles that we consume

in normal diets. Furthermore, the levels of insulin in the subjects were not

chronically high, as one finds in type-2 diabetes, and the glucose curves were

normal for all groups. The study tells us nothing about what happens in real

life with people eating real food.

The second study looked at a small group of subjects—a total of 17—who were

told to follow a diet rich in saturated (by using more dairy products) or

polyunsaturated fatty acids (by using more oils and spreads) for five weeks.

When on the saturated fat diet, the subjects had a slightly lower measure of

insulin sensitivity but glucose levels and body mass indices were virtually

identical.

Again, this study has little to do with real life. The actual amount of

saturated or polyunsaturated fat (or trans fat) in each diet was not measured

and

the number of subjects was too small to be meaningful.

Neither of these studies tells us what happens in real life in subjects who

eat a diet high in natural saturated fats compared to those whose diets

contain a lot of vegetable oils. The fact that the researchers are strong in

their

condemnation of saturated fats after such trivial findings is strong

evidence of bias.

The real problem is that recommendations to avoid saturated fats almost

invariably result in people consuming more trans fats. There is no question but

that the trans fats have been shown to have a detrimental effect on the

incidence and treatment of type-2 diabetes. The saturated fats, on the other

hand,

have no effect when appropriate comparisons are made.3

Very good studies indicate that trans fats interfere with insulin receptors

and therefore with insulin resistance. The saturated fats do not.4

The recommendations regarding dietary saturated fats intake versus trans

fats intake for the past number of years have been very confusing to the

public,

and judging from the articles, also confusing to the researchers. Trans fats

are mistaken by many of the health professionals for saturated fats although

they are not similar in their effects on the human body, just similar in the

manner of stability in the baking or cooking realm.

" So Many Nutrition Recommendations Contradictory or Compatible? " written by

a major dietitian from the American Dietetic Association lists the amounts of

fat and different fats that are acceptable. According to their

recommendations, total fats could represent 20-35 percent of the calories in the

diets of

individuals as listed in the Dietary Reference Intakes, 25-35 percent as

called for by the National Cholesterol Education Program, but the American

Diabetes Association says that fat intake should be individualized (expert

consensus). However, recommendations for the type of fat mixes the saturated

fats and

the trans fats, as do almost all of the writers in these organizations. The

report notes that a diet with only 5 percent of the total energy from

saturated fats is adequate; and yet research shows that the normal level of

saturated fats in the tissues is much higher.5

Another example of inappropriate conclusions drawn from a research project

comes from Colorado State University, where researchers decided that a

" saturated fat byproduct " was a potential contributor to type-2 diabetes. This

so-called saturated fat metabolite is ceramide. Ceramide is a lipid molecule

made

in the body from something called sphingosine and a fatty acid (which could

be oleic acid, a so-called good fatty acid). This molecule is used to make

sphingomyelin, which is one of the structural elements in the lipid bilayer, as

well as being a cellular signal molecule. Sphingomyelin is one of the lipid

building blocks of the myelin sheath so important for nerves.

Ceramides are interesting molecules currently being studied for a role in

programmed cell death, and substances known to induce ceramide production are

components such as endotoxins and chemotherapeutic agents more likely to be

from the stress of trans fats than from the normal saturated fats, which are

such important building blocks of our tissues. The saturated fat in the study

was based on in vitro measures of free fatty acids and therefore does not

represent a diet intake.6

In summary, the studies cited by your professor and others do not represent

what happens in the real world with people eating real food. Think of it this

way: type-2 diabetes is a new disease, one that has now reached epidemic

proportions. Type-2 diabetes did not exist 100 years ago when our diets were

very rich in saturated fats. Type-2 diabetes appeared when trans fats came into

the diet, and has become epidemic as people are eating more and more foods

containing trans fats. And since we know that trans fats interfere with insulin

receptors in the cells, it is clear that the blame lies with new industrial

fats, not traditional saturated fats.

REFERENCES

1. Robertson MD and others. Acute effects of meal fatty acid composition

on insulin sensitivity in healthy post-menopausal women. British Journal of

Nutrition 2002 88, 635-640.

2. Summers LK and others. Diabetologia 2002 mar;45(3):369-77.

3. Hu FB and others. Diet lifestyle and the risk of type 2 diabetes

mellitus in women. New England Journal of Medicine 2001, 345: 790-7; American

Journal of Clinical Nutrition June 2001, 73: 1001-1002, 019-1020.)

4. Research by Barnard, Dennis, University of Maryland and USDA.

5. Marion J, Franz, MS,RD,LD,CDAE, Task Force Chair, ADA.

6. Chavez JA and others. Acid ceramidase overexpression prevents the

inhibitory effects of saturated fatty acids on insulin signaling. Journal of

Biological Chemistry 2005 280:20148-53.

 

About the AuthorMary G. Enig, PhD is an expert of international renown in

the field of lipid biochemistry. She has headed a number of studies on the

content and effects of trans fatty acids in America and Israel, and has

successfully challenged government assertions that dietary animal fat causes

cancer

and heart disease. Recent scientific and media attention on the possible

adverse health effects of trans fatty acids has brought increased attention to

her

work. She is a licensed nutritionist, certified by the Certification Board

for Nutrition Specialists, a qualified expert witness, nutrition consultant to

individuals, industry and state and federal governments, contributing editor

to a number of scientific publications, Fellow of the American College of

Nutrition and President of the Maryland Nutritionists Association. She is the

author of over 60 technical papers and presentations, as well as a popular

lecturer. Dr. Enig is currently working on the exploratory development of an

adjunct therapy for AIDS using complete medium chain saturated fatty acids from

whole foods. She is Vice-President of the Weston A Price Foundation and

Scientific Editor of Wise Traditions as well as the author of Know Your Fats:

The

Complete Primer for Understanding the Nutrition of Fats, Oils, and

Cholesterol, Bethesda Press, May 2000. She is the mother of three healthy

children

brought up on whole foods including butter, cream, eggs and meat. See her

website

at _http://www.enig.com/trans.html_ (http://www.enig.com/trans.html) .