Food Diets

Low-Carbohydrate Diet

Carbohydrate-restricted eating, compared head-to-head with low-fat dieting in the DIETFITS randomised trial published in JAMA.

A low-carbohydrate diet restricts carbohydrate-dense foods — bread, pasta, rice, sugary foods and drinks — and replaces the calories mainly with protein and fat. The StatPearls clinical reference on the NCBI Bookshelf notes there is no single agreed definition; definitions in research range from under 130 g of carbohydrate per day down to the very-low (ketogenic) range below about 50 g.

What published research reports

The DIETFITS randomised clinical trial, published in JAMA in 2018, assigned 609 overweight adults to a healthy low-fat or healthy low-carbohydrate diet for 12 months. Weight loss was 5.3 kg in the low-fat group and 6.0 kg in the low-carbohydrate group — a difference that was not statistically significant. The trial also reported that neither genotype pattern nor baseline insulin secretion predicted which diet worked better for a given person. Both groups were coached to emphasise vegetables and whole foods and to limit sugar and refined flour.

References

Gardner CD, et al. Effect of Low-Fat vs Low-Carbohydrate Diet on 12-Month Weight Loss in Overweight Adults (DIETFITS). JAMA. 2018;319(7):667–679. PubMed · JAMA
Oh R, Gilani B, Uppaluri KR. Low-Carbohydrate Diet. In: StatPearls [Internet]. National Library of Medicine, NCBI Bookshelf. ncbi.nlm.nih.gov