Research

Energy balance

Ad libitum low-fat diets produce a statistically significant, dose-dependent weight loss in overweight individuals without requiring active energy restriction.

To lose weight without counting calories, reduce the percentage of your daily energy coming from fat. This meta-analysis shows that simply lowering fat intake (while eating ad libitum) leads to an average loss of about 2.5 kg in overweight individuals over several months. The key is that low-fat foods are less energy-dense, which naturally reduces total calorie intake.

GoodSupportsHIGH confidence
The weighted difference in weight loss between intervention and control groups was 2.55 kg (95 % CI, 1.5–3.5; P < 0.0001)... A reduction in dietary fat without restriction of total energy intake prevents weight gain in subjects of normal weight and produces a weight loss in overweight subjects.
Arne Astrup et al. · British Journal Of Nutrition · 2000

Why this rating

Meta-analysis of 16 randomized controlled trials with 1728 participants, though excluding obese subjects and noting variability.

Source

The role of dietary fat in body fatness: evidence from a preliminary meta-analysis of ad libitum low-fat dietary intervention studies

Arne Astrup et al. · British Journal Of Nutrition · 2000

DOI 10.1017/s0007114500000921

Meta-analysis · 16 studiesCited 289×
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DOI resolved against Crossref · corpus check 2026-06-10

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