For the longest time, “healthy eating” and “low fat diet” have been virtually synonymous. Low-fat diets are still popular among people trying to lose weight, as well as people trying to prevent or help treat heart disease.
Even many athletes will consume low fat diets. Unfortunately, this may compromise their endurance. According to the Department of Physical Therapy, University at Buffalo, New York, in “The effects of varying dietary fat on performance and metabolism in trained male and female runners“:
Runners on the low fat diet ate 19% fewer calories than on the medium or high fat diets. Body weight, percent body fat (males=71 kg and 16%; females=57 kg and 19%), VO2max and anaerobic power were not affected by the level of dietary fat. Endurance time increased from the low fat to medium fat diet by 14%. No differences were seen in plasma lactate, glucose, glycerol, triglycerides and fatty acids when comparing the low versus the medium fat diet. Subjects who increased dietary fat to 44% had higher plasma pyruvate (46%) and lower lactate levels (39%) after the endurance run.
These results suggest that runners on a low fat diet consume fewer calories and have reduced endurance performance than on a medium or high fat diet. A high fat diet, providing sufficient total calories, does not compromise anaerobic power.
So if you’re an endurance athlete, a low fat diet may hurt your performance. Just a little more can lead to significant improvements.
Fat of course is a vital macro-nutrient, but the idea that fat is bad for you and will quickly lead to weight gain is still very pervasive. The truth is actually a lot more complicated than this.
Generally speaking, plant fat is healthier than animal fat. In particular, mono-unsaturated fats like olive oil, and almond oil are heart healthy, unlike animal fat which is saturated and more likely to clog arteries. Mono-unsaturated fats tend to be liquid, while saturated fats are thicker, chunkier, and semi-solid. Fat is also better raw, since cooking it can make it unstable and more likely to promote inflammation.
Trans-fats are the absolute worst and should be avoided at all costs. It’s like they were invented by evil scientists for the purpose of causing heart attacks. Omega 3 fats, which are abundant in flaxseed, walnuts, oily fish and certain species of algae are also good for you. The jury is still out on the long-term health effects of coconut oil, which is one of the very few plant sources of saturated fat.
As for me, I tend to eat a moderate to high fat vegan diet. I eat a lot of nuts and often consume a lot of olive oil. In my case it is justified since I usually run over 40 miles per week. I usually prefer fat raw, but I am okay with lightly cooking it sometimes.
Besides avoiding trans-fats, I also avoid palm oil. This is because palm oil production is largely responsible for the massive deforestation in South-East Asia, threatening to drive the Orangutan and countless other species extinct.