ISSN 1662-4009 (online)

ESPE Yearbook of Paediatric Endocrinology (2019) 16 12.9 | DOI: 10.1530/ey.16.12.9


Lancet Public Health 2018;3:e419–e428.
DOI 10.1016/S2468-2667(18)30135-X
URL: http://www.ncbi.nlm.nih.gov/pubmed/30122560

Summary: The long-term effects on health outcomes of dietary carbohydrate intake was investigated in a large prospective cohort of 15,428 US adults aged 45–64 years with 25 years follow-up. Both low carbohydrate consumption (<40%) and high carbohydrate consumption (>70%) conferred greater mortality risk, with minimal risk observed at 50–55% carbohydrate intake. Of note, mortality increased when carbohydrates were exchanged for animal-derived fat or protein, and mortality decreased when the substitutions were plant-based.

Comment: It appears that the very basic and seemingly simple thing in life, to eat, has become complicated and controversial. Fierce debate about the right way to eat pervades in social networks, with diverse opinions. Professional recommendations from the fields of medicine and nutrition have shifted from one extreme to another – low fat – low carb – low protein –diets have all been claimed as means of improving our health and losing weight. After many years during which fats were considered the number one enemy, the current fad is to cut back on carbohydrates.

The association of the percentage of energy intake from carbohydrates with all-cause mortality was assessed in 15,428 adults aged 45–64 years, based on a dietary questionnaire administered at two intervals, spanning a 6-year period. In addition, data from seven multinational prospective studies including 432,179 participants were analyzed.

A U-shaped relationship was observed between carbohydrate intake and mortality. Low carbohydrate diets, which generally result in lower intake of vegetables, fruits and grains, and increased intake of protein from animal sources, have been hypothesized to stimulate inflammatory pathways, biological ageing and oxidative stress. The substitution of animal compared with plant sources of fat and protein was found to increase the risk of mortality. On the other end of the spectrum, high carbohydrate diets confer a chronically high glycemic load that can lead to negative metabolic consequences.

The science behind fad diets is extremely important, and as concluded here, the anti-carb fad should be viewed, as any extreme fad – i.e. with caution.