nutrition

According to an unpublished study presented at a conference of the American Heart Association and not peer-reviewed, an analysis of over 20,000 American adults found that individuals who restricted their food intake to less than 8 hours a day, following a time-restricted eating plan, were more likely to die from cardiovascular diseases compared to those who ate during 12-16 hours a day.

Eating more ultra-processed foods is linked to a higher risk of health problems, according to an umbrella review of 45 previous meta-analyses, involving almost 10 million people in total. The research, published in The BMJ, finds direct associations between exposure to ultra-processed foods and 32 health parameters. The strongest evidence links this exposure to cardiometabolic health problems, mental disorders and overall mortality.

A dietary shift from animal-based foods, such as red or processed meat and eggs, to plant-based foods, such as nuts, pulses and whole grains, is associated with a reduced risk of death and diabetes or cardiovascular disease. For example, replacing 50 grams of processed meat per day with 28-50 grams of nuts is associated with a 27% decrease in cardiovascular risk. These are the conclusions of a systematic review of 37 studies published in the journal BMC Medicine.

A US research team has identified several genes that may be associated with a strict vegetarian diet. Some of these genes have "important roles in lipid metabolism and brain function", according to the paper, which suggests that these differences could explain the ability to subsist on a vegetarian diet in those who carry these genes. The study, published in the journal PLoS ONE, used data from the UK Biobank to compare a group of more than 5,000 vegetarians with a group of more than 320,000 non-vegetarians.

A study in mice found "mild metabolic and neuropsychological malprogramming" in the offspring of females who, during gestation and lactation, had ingested emulsifiers, substances used to improve the texture of ultra-processed foods. The article, led by a team from IDIBAPS in Barcelona and published in PLoS Biology, states that the consumption during these periods of carboxymethylcellulose and polysorbate 80 - two common emulsifiers - diluted in water was associated with metabolic and cognitive deficits in the mouse offspring.

The International Agency for Research on Cancer (IARC) and the Joint FAO/WHO Expert Committee on Food Additives (JECFA) have published a health impact assessment of the sweetener aspartame. Citing "limited evidence" of carcinogenicity in humans, IARC has classified aspartame as possibly carcinogenic to humans (Group 2B). For its part, JECFA has not changed the acceptable daily intake of this sweetener, which is set at 40 mg/kg body weight. According to these bodies, with one can of diet soft drink containing 200-300 mg aspartame, a 70 kg adult would need to consume more than 9-14 cans per day to exceed the acceptable daily intake - assuming no other intake from other dietary sources.

Reuters has reported that aspartame, one of the most common artificial sweeteners, will be listed as "possibly carcinogenic to humans" by the International Agency for Research on Cancer (IARC), an agency of the World Health Organisation, in July.

The WHO has issued a new guideline advising against the use of non-sweetened sweeteners for weight control or to reduce the risk of noncommunicable diseases. The recommendation is based on the findings of a systematic review published in 2022.

A new scientific statement from the American Heart Association published in the journal Circulation analyzes how several diets (including Mediterranean, Paleo, and ketogenic) fit into the guidelines for a heart-healthy diet. The ketogenic and 'paleo' diets were not classified as heart-healthy.

A study in mice has found that high doses of the sweetener sucralose can reduce the immune response and, under certain laboratory conditions, alter its action against infections or tumours. The results are published in the journal Nature.