Low-fat Dietary Pattern and Risk of Cardiovascular Disease
February 05, 2006Low-fat Dietary Pattern and Risk of Cardiovascular Disease
Number 124 Reference: JAMA. 2006 Feb 8;295(6):655-66
This is a very interesting NIH study. It cost over $ 451 million to conduct. Over 48,000 women followed prospectively for an average of 8.1 years. Half were told how to eat less fat. The others were simply given literature about how to eat better. This was started back in the days when we thought low fat was nirvana. (As we now know, the low-fat mantra was not matched with low calorie and America gained a pound a year per person during that era by eating more calories: that's the background)
The study women indeed reduced their fat intake from around 35-40 % to 24-29% of daily calories. There was no identified benefit to a reduced fat intake. No reduction in cancer, heart attack, stroke. Study patients had a trend to fewer breast cancers that were not statistically significant, and fewer colon polyps, which turn into cancers.
Was the study a bust? This study will be quoted for years. Here is the nuance for you to understand its context. Here is the conjecture published so far. 1. All the women were started after age 50 and menopause. That may be too late. We may need lifelong habits. 2. No effort was made to reduce weight. That may be part of the story (I agree) 3. 8.1 years may be too short a period to tell. (My opinion. My belief is the benefits take 25-40 years to show in full) 4.No effort to eat good fats (olive oil) versus bad fats (trans fats and sat fats) was made. That may be crucial. (I agree) 5.No correlation with exercise. (That may be bigger still)
My other opinions: no clear focus on fiber. Most women were probably below 40 grams as most Americans eat 25 grams of fiber a day. No focus on the benefits of the DASH diet with its whole grain, abundant fruits and veggies, and dairy servings every day. And, let me slip in, no Vitamin D!
This confusion lends credence to the frustration we all feel as research continues. Don't let it. I think it underlines the importance of lifelong habits. The story of inflammation and how the metabolic processes in our body mesh with long-term risk is yet untold. We do know that our fat tissue is not a passive storage site but actually metabolically very active, making LOTS of inflammatory hormones. There will be more to come on that later this year when we talk about the Endocannabinoid System. This study was put together before we realized the catastrophe of the "low fat" strategy when we didn't tie it to lower calorie control.
High monounsaturated fat diets (olive oil) are the foundation of the Mediterranean diet.
www. What will work for me? I continue to eat GOOD fat. Lots of olive oil is fine, if not good for you. I avoid TRANS fats like they were poisons. And I'm avoiding refined grain foods: whole grains are better. And I struggle to lose weight. We are in this for the long haul. I intend to live longer than 8.1 more years. The investment I'm making in me at age 54 will pay off at age 84. As best as I can tell from this research, I will have lower blood pressure, fewer colon polyps, and less breast cancer. Anyone want to schedule a golf game with me on my 84th birthday? That's what we want for each other. Community, support, and activity for the long haul.
This column is written by Dr. John E. Whitcomb, MD, Brookfield Longevity, Brookfield, WI, (262-7844-5300)