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American Heart Assoc & Low Carb

The American Heart Association is now recommending a lower carb diet for prevention of cardiovascular heart disease, heralding the beginning of the Low Carb Age!

A new study, recently presented at the American Heart Association annual meeting in Orlando, FL, tested the effect of a low fat verses moderate fat diet. The low fat diet contained 20 percent of calories from fat, 65 percent from carbs and 15 percent from protein (this is the standard low fat diet that has been recommended for years). The “moderate fat diet” increases fat, and to keep the calories consistent, lowers the carbohydrate contribution. The moderate fat diet in the study has 40 percent of the calories from fat, 45 percent from carbohydrate and 15 percent protein. HealthDay, from the National Institutes of Health, quotes the AHA:

“This is a good study that essentially confirms that the current recommendations are appropriate,” said Alice Lichtenstein, a spokeswoman for the American Heart Association (AHA). “Since 2000, the AHA has been recommending not a low-fat diet, but one that is low in saturated fats and trans fatty acids.”

People with metabolic syndrome are glucose-intolerant, meaning they can’t process blood sugar well. Low-fat, high-carbohydrate diets exacerbate this condition, Lichtenstein explained.

The study is explained in more detail on our Diabetes and Metabolic Syndrome research page. The conclusion of the study gives the bottom line:

Conclusions: This is the first study to examine the effects of low fat vs. moderate fat diet in MetS. MF compared to LF diet improves the atherogenic dyslipidemia of MetS. MF diet is a preferable dietary intervention in people with MetS to improve CVD risk.

Whew. What the heck does that mean? Here’s a layman’s plain English translation:

This is the first study to examine the effects of low fat vs. a moderate fat diet with lower carbohydrates in patients with metabolic syndrome. The moderate fat diet compared to the low fat diet improves the heart disease related risks of various blood fats (VLDL, LDL, triglycerides, etc.) in people with metabolic syndrome. The moderate fat diet is therefore a better diet for people with metabolic syndrome.

Health Day goes on to quote other experts:

Experts familiar with the study aren’t surprised by the findings. “This sort of falls within the boundaries of what we used to call the Atkins diet, which was a high-lipid and low-carb diet. Normally this kind of diet suppresses appetite, improves diabetes,” said Dr. Alfred Bove, president of the American College of Cardiology. “This diet looks like it does a good job of altering the negative metabolic effects of early diabetes or high carbohydrate stimulation,” he said.

“Much of this we’ve known before, but the idea is that a moderate-fat diet is something most people can tolerate,” Bove said. “It probably affects the way insulin is released because if you have a lot of carbohydrates in the diet, you tend to generate a lot of insulin, and insulin is the hormone that lowers blood sugar,” Bove explained. “In addition to lowering blood sugar, it also increases appetite so a lot of people on high-carb diets are restimulated to eat more.”

Low Carb Better than Low Fat

Another article has been posted to our Research pages, this time recapping a study that compared a standard LCD (low carb diet) to the American Heart Association diet that emphasizes low fat. The study was published in the Nutrition, Metabolism and Cardiovascular Diseases journal, and is posted here.

The study selected 39 individuals and divided them into two groups. One group ate a carb-restricted diet for 12 weeks. The other group ate a carb-restricted diet for 6 weeks, and then switched to the AHA diet for the remaining 6 weeks.

In this study, the low carbohydrate diet followed the recommendations of most of the low carb diets: 20 to 25% of calories from carbs. The AHA diet, by comparison, doubles that amount with 50 to 55% of the calories from carbs.

One concern often expressed about eating low carb and increasing saturated fat in the diet is that LDL can rise using the normal calculated value. This study looks specifically at the type of LDL that each of the diets produces, using direct measurements rather than an inaccurate calculation.

The short version of the results is that the low carb diet “had a better effect on atherogenic VLDL and HDL than the low fat diet recommended by AHA.” Atherogenic VLDL and HDL are particles that lead to the formation of atheromas on the walls of the arteries, or what we commonly call atherosclerosis.

This is just one study, and won’t immediately change the dietary recommendations of nutritionists, doctors and the American Heart Association. But the “Low Fat Age” is seeing its reign come to an end, and the Low Carb Age is upon us.

Low Carb Diets – Evidence Mounts

We added a few more links to our Research Pages, including two new studies showing that a low carb diet works better than the traditional low fat diet for metabolic syndrome (scroll to bottom for the section on metabolic syndrome).

I found these studies through a column that is good, but not great. The LA Examiner online has an article about low carb diets and CHD (coronary heart disease). The studies they link to regarding inflammation at the Cleveland Clinic do not mention high carbohydrate diets at all. It is a bit misleading; the author states categorically that inflammation is caused by several factors including “over consumption of processed carbohydrates”, and then links to the Cleveland Clinic article. But I cannot find that sentiment on any of the Cleveland Clinic’s linked pages; they advocate the low fat, high complex carbohydrate diet instead.

The article is valuable for the links to other studies and resources that do connect a low carb diet to reduced inflammation. If the reader checked the Cleveland Clinic source and went no further, he would have to conclude the author is incorrect and may dismiss the article. So check out the other links and information provided.