sandy kenny

The percent composition of your diet depends on the denominator (total caloric intake) as well as the numerator (say, fat intake). Hitting a 20-25% target for fat intake is more important if you are eating close to the "normal" RDA of energy (kilocalories). 20% of 2500 is 500 kcal or about 55-60 grams of fat per day, of which the experts say no more than 20 should be saturated fats. Fats are needed for cell synthesis, tissue maintenance, and hormone balance.



If you're working out strenuously and trying to maintain muscle mass and glycogen stores, you will need more food than that. If you add protein (muscle mass) and carbohydrate (glycogen) to your diet, your denominator increases, but the numerator stays about the same, so the % of fat in your diet decreases. Some added fat will "sneak" in on the extra buttered bread, olive oil'd pasta,nuts, or meats, of course. But, if you're concentrating on high-quality chow, and eating above the RDA for total energy, it's probably okay to go lower in fat as a total % of your diet by adding mainly carbs and protein to an otherwise balanced diet.



Exercise, espceially long-term endurance exercise, blunts the insulin response to simple carbohydrate. Many top ultraendurance cyclists ride for 24-48 hours supplemented mainly by gummy worms and flat Coke. I think this sounds yukky, but on the other hand my gotta-have emergency fuel is York Peppermint Patties. I don't see a lot of complex carbs there!



The blunting effect works best if you have been exercising for an hour or more BEFORE you ingest the carbs.