This article is from the Misc Bicycles FAQs, by various authors.
Though cholesterol levels are rarely a problem for racing
cyclists, a high fat diet can effect performance, especially for track
and criterium riders. Fat is not very nutrient-dense. Those nine
calories per gram displace proteins and carbohydrates and are rarely
high in vitamins or minerals. While fats play an important role in
hormone production and nerve cell function, especially in children and
young adults, the U.S. national average of 40%+ of calories derived
from fat is well over the recommended 25 to 35%.