Fats In The Human Body, Part 1: Body Fat And Diet
Next to water, which makes up about 70% of the total weight of a human adult, and 84% of that of a newborn infant, fat is the most abundant substance found in our body. We may not like that, but there it is.
The exact amount of fat present in the body is influenced by diet, exercise, age, gender, and genetic disposition, and can vary from 5% to over 60%, with an average of 15 to 22%. Degenerative diseases are associated with both overweight and underweight.
Concentrated high-calorie foods – those rich in refined sugars, starches, proteins, and saturated fats, and low in fiber and water – increase fat deposition. When we gain weight, the extra ‘weight’ is plain old fat unless we gain muscle through strenuous physical activity. Bulky foods rich in water and fiber, such as leafy vegetables, tend to keep us slim.
Athletes need to be more slim and trim than average. Extra fat during competition means that their muscles must do more work, which could cost them the medals they aim to win. Male swimmers trim down to 12% fat, runners down to 8%. Women athletes usually trim down to around 15%. World class body builders carry 12% fat between competitions, and go down to 6% body fat during competition, for better cut and definition of muscle profile.
Although it is possible for women to lose most of their fat, this may not be desirable from a health point of view, as low body fat may affect female hormonal balance. Olympic and other female athletes often lose their menstrual cycles. Loss of the menstrual cycle is also one diagnostic sign of the eating disorder anorexia nervosa.
The best way to lose excess fat is to build muscle. Losing fat through the use of self-imposed starvation diets is self- defeating in terms of health and, in the long run, even for weight loss. Liposuction – the high-tech, expert-administered alternative – is safer than starvation, but undermines personal initiative and responsibility.
Exercise, good food choices, and thinking (or visualizing) ‘slim’ are the three keys to successful slimming. During exercise, our muscles consume fat to produce energy.
Fat deposits around our entire body are rearranged and reduced when we exercise. Since muscle weighs more than fat, exercising may actually increase weight rather than decrease it, but an exercised body looks slimmer and feels better. Our bathroom scales are therefore less reliable than mirror, eyes, and feelings.