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Effect of cutting down the fat we eat on body weight

The ideal proportion of energy from fat in our food and its relation to body fatness is not clear. This review looked at the effect of cutting down the proportion of energy from fat in our food on body fatness in adults who are not aiming to lose weight. Body fatness was measured using body weight, body mass index, waist circumference and percent body fatness. The evidence is current to October 2019. The review found that cutting down on the proportion of fat in our food leads to a small but noticeable decrease in body weight, body mass index, percentage body fat and waist circumference. The effect did not change over time, but reducing fat intake to a greater extent results in greater weight reduction. We assessed potential harms of reducing total fat, but found no evidence of harm on serum lipids, blood pressure or quality of life.