Research
Energy balance
Reducing total dietary fat to 30% or less of calories, and saturated fat to less than 10%, is unlikely to have a substantial, sustained effect on body fatness or breast cancer risk, although it may modestly reduce CHD mortality.
Don't expect that simply cutting fat to 30% of your calories will lead to significant long-term weight loss or breast cancer risk reduction. Focus on overall diet quality, including vegetables, fruits, and whole grains, rather than just fat percentage.
GoodRefutesHIGH confidence
The available evidence suggests that reductions in dietary fat composition over the ranges currently recommended are not likely to have a substantial, sustained effect on body fatness. The recommended moderate reduction in dietary fat (2) is likely to have little effect on breast cancer risk...
Why this rating
Based on randomized trials and prospective studies showing little long-term effect on body weight or breast cancer risk from moderate fat reduction.
Source
Diet and Health: What Should We Eat?
Walter C. Willett · Science · 1994
DOI 10.1126/science.8160011
narrative_reviewCited 1,012×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
More from this paper
- Replacing saturated fats with monounsaturated or polyunsaturated fats reduces LDL cholesterol without lowering HDL, thereby reducing coronary heart disease risk, whereas replacing saturated fats with carbohydrates may lower HDL and reduce the predicted benefit.Good
- High intake of trans fatty acids (partially hydrogenated vegetable fats) increases the risk of coronary heart disease by lowering HDL and raising LDL and lipoprotein(a).Good
- High consumption of vegetables and fruits is associated with a significantly reduced risk of various cancers, including lung, stomach, colon, and oral cancers, primarily due to micronutrients like carotenoids, vitamin C, and folic acid.Good
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