Perspectives: do alcohol calories count?

Article Abstract:

The effects of alcohol on energy balance and body weight are complex. Alcohol contains a lot of calories but it reduces the absorption of nutrients from the diet and alters the digestion and metabolism of carbohydrates and fat. Since alcohol is high in calories one might expect alcohol to cause weight gain. However, alcoholics are no more obese than nondrinkers, and in women alcoholism is associated with low body weight. It appears that the effects of alcohol on body weight depend on the amount of alcohol consumed and the fat content of the diet. Alcoholics can consume almost 50 percent of their total daily energy intake in the form of ethanol. When large amounts of alcohol are consumed on a regular basis liver enzymes involved in fat metabolism become damaged. Studies in laboratory rats and humans have shown that a diet containing 36 percent of the total energy in the form of alcohol and 35 percent fat resulted in less weight gain than a diet containing 36 percent alcohol and 5 percent fat. To investigate this issue further, 14 alcoholics were studied. For the first seven days of the study each subject followed a balanced diet with just enough calories to maintain their normal body weight. Between days 9 and 16, dietary carbohydrates were replaced with ethanol until ethanol accounted for 50 percent of the total daily calories. By day 16 of the study, the subjects had lost an average of 2 pounds. When ethanol was consumed as an addition to a balanced diet, with normal carbohydrate content, slight increases in weight gain were observed. The results of this study combined with those of previous studies indicate that chronic alcohol consumption impairs the body's ability to metabolize dietary fat and use it as a source of energy. Replacing dietary fat with carbohydrates may help to maintain body weight in alcoholics and patients with liver disease. (Consumer Summary produced by Reliance Medical Information, Inc.)

Author: Lieber, Charles S.

Publisher: American Society for Clinical Nutrition, Inc.

Publication Name: American Journal of Clinical Nutrition

Subject: Health

ISSN: 0002-9165

Year: 1991



Evaluation, Measurement, Food and nutrition, Alcohol, Ethanol, Body weight, Fat metabolism, Alcoholics

Resting energy expenditure and substrate oxidation in human immunodeficiency virus (HIV)-infected asymptomatic men: HIV affects host metabolism in the early asymptomatic stage

Article Abstract:

Patients with AIDS frequently experience severe weight loss. This may be caused by malabsorption of nutrients by the digestive tract, poor diet, or changes in metabolism resulting in increased energy (calorie) expenditure. A previous study suggested that patients with AIDS have an increase in resting energy expenditure (REE), but this might have been due to hidden opportunistic infections rather than infection with HIV (human immunodeficiency virus, the cause of AIDS). To clarify this issue, metabolism in 11 male patients with asymptomatic HIV infection was studied as was that of 11 healthy control subjects. Infected patients had normal levels of T lymphocytes, the immune system cells which are eventually destroyed during the progression of AIDS. Infected patients tended to be significantly shorter and had lower body weight and lower levels of absolute fat-free mass (FFM), but the relative percentages of body fat and FFM per total body weight were similar in the groups. Despite lower absolute FFM in infected patients, REE did not differ between groups, which is indicative of relative hypermetabolism (i.e. overactive metabolism) in infected individuals. On average, patients had 8 percent higher rates of REE. The only observed metabolic difference which could contribute to this was an increase in the rate of fat oxidation (breakdown and usage for energy). Infected patients also had higher blood levels of the adrenalin-like neurotransmitter norepinephrine (a hormone which stimulates nerves) and of interleukin-6, which is an immune system hormone. The study indicates that HIV infection affects metabolism early in the disease, before symptoms are apparent. (Consumer Summary produced by Reliance Medical Information, Inc.)

Author: Sauerwein, Hans P., Hommes, Mirjam J.T., Romijn, Johannes A., Endert, Erik

Publisher: American Society for Clinical Nutrition, Inc.

Publication Name: American Journal of Clinical Nutrition

Subject: Health

ISSN: 0002-9165

Year: 1991



Physiological aspects, HIV infection, HIV infections

Subjects list: Health aspects, Energy metabolism