I am still wrestling with the question of the ideal fat percentage in my eating plan. I had a very interesting discussion with Jeff Novick on his discussion forum about the subject. Follow this link to see the full discussion.
In sum, Jeff thinks that fat consumption is not the ideal way to get extra calories for endurance sports. To be clear, he does recommend getting adequate Omega 3 fats and other essential fats, but think that all the "essential" fat we need can come form a low fat, plant-based diet.
Jeff does not specify the ideal fat %, but reading the discussions on his website would lead me to believe that he considers 10-15% fat to be fine for most people. He does not buy into the theory (Dr. Fuhrman's theory) that low fat diets lead to arrhythmia and other conditions of the nervous system as we age. Novick says that there is no research that supports the concern that low fat diets lead to arrhythmia.
Dr. Fuhrman, on the other hand, recommends not eating a low fat diet <15% and has the following bottom line recommendation.
My experience, and that of my nutritional buddy, Kneecap, has been that a low fat diet does seem to aggravate arrhythmia. We both have been arrhythmia-free since starting Fuhrman's program, with a higher healthy fat consumption, and cutting out all added salt. We suspect that eliminating added salt was also of major benefit. See my writeup on the subject and Kneecap's additional comments.
Dr. Fuhrman says that an active person can (should) consume much more than 15% fat in the diet as long as the fat is from whole plant food natural sources, ie, raw nuts, seeds, and avocados. He also supports fish oil supplementation, if the fish oil caps have been purified and contain no mercury and other contaminants. Dr. Fuhrman even supports fat % consumption up to 50% per day for very active people who eat a healthy diet and who get their fat from nuts/seeds/avocados.
Since I am very active and have had arrhythmia problems, should I follow Dr. Fuhrman's advice, or should I keep my fat intake low?
What are the arguments for a low fat diet? Dr. Esselstyn says that those with heart disease can reverse their disease with a low fat diet. Dr. Ornish's research supports this. The physicians who support low fat, are concerned that too much fat causes blood vessel inflammation that leads to heart disease. These doctors are concerned (although can't prove) that more than 2 oz. of so of nuts/seeds might cause the same blood vessel inflammation as saturated fat. Vegetable oils have not been given a clean bill of health by these physicians. Again, Dr. Fuhrman thinks a diet with fat consumption as low as 10% can lead to health problems such as arrhythmia and Parkinson's Disease as we age. According to Novick, all the research showing the benefits of nuts/seeds have been on populations who consume less than 2 oz. per day.
As is often the case with nutritional "science", the experts don't agree. But, are we making too much of the differences. I find it hard to believe that any of these physicians would argue against a healthy plant-based diet with 15-20% fat from whole foods sources, as long as the individual was free of heart disease, and maintained a healthy weight.
So what is a healthy weight. Jeff Novick says the longest-lived people have BMI's between 18 and 22. If I got down to 22, I would weigh 158 pounds, which seems too light for my build, which tends towards the muscular. I might be kidding myself, but a BMI of 23 seems about right for me, which would put me at 165. My height is 5'11", and current weight is 172.
Here is my tentative conclusion based upon my personal experience and common sense, not on any research other than the reading I have already cited. Admittedly, there is some guess-work involved.
1. In using a nutritional analysis program CRONO-O-METER and analyzing my diet for two weeks, it appears that I can get all the essential fat I need by taking a vegan DHA supplement (1 ml of Dr. Fuhrman's DHA Purity), 1 tbsp of ground flaxseeds, and 1-2 oz. of raw nuts/seeds per day. During the period February 7 to February 20, 2009 I have mostly limited my fat intake to this level although I have gone above 2 oz. of raw nuts/seeds on a couple of days. The result has been that I get over 100% of Omega 3 and Omega 6 fats with this fat intake. My ratio of Omega 6/Omega 3 fats during this period was about 4/1, which I understand to be the current thinking as to the right ratio. Therefore, there is likely no real health benefits from consuming more fat than this.
2. At this level of fat intake, by daily fat % is about 20, somedays closer to 15%. The question is, therefore, should I take in more fat, to get the needed added calories, on days when doing hard long cycle training? I am going to experiment with getting these calories from additional starchy vegetables, rather than additional fat, as stated in this post. On days that I train, I will eat more oatmeal, sweet potatoes, pasta, white potatoes, etc., keeping my fat intake to 15-20%of total calories.
3. I do not intend to be a slave to this. Once I reach my ideal weight range - 165 - 169 (or a BMI of 23-23.6) I see no reason not to eat more than 20% on some days, as long as I don't make a habit of high fat consumption. Under all circumstances the vast majority of all the fat I consume will come from raw nuts/seeds and avocados.
4. If I stay around 15-20% fat intake, maintain my ideal weight, and have the energy to train as hard as I would like, I should be optimizing my health. I don't expect any more problems with arrhythmia, but who knows?
5. The target weight range that I have set, 165-169 is guesswork. A BMI of 22 (158 pounds) seems too light for me and probably would require me to lose muscle mass. I don't think losing muscle is a good idea as I age. As a younger man, when I was doing marathon running, my weight never went below 162, and at this level I felt somewhat weak. There might be some life extension benefits to me getting to a BMI of 22 or below, but, for now at least, I am going to be happy at 23-23.5. I am hoping that I can maintain this weight on a diet that contains 15-20% fat from healthy sources.
All of this is subject to change as I continue to experiment. I find the topic of nutrition to be very interesting.