If you search for "diets" on Google, you will get about 34.9-million hits in 0.31 seconds.
As the world gets fatter and obesity finds its way on to every nation's health agenda, people are fixating on ways to lose weight. Choices include the paleo diet, the vegetarian diet, the South Beach diet, the raw food diet and the Weight Watchers diet. Some say you must cut out carbohydrates; others that you must count your calories.
The most unsuccessful diet I've heard of was the Coca-Cola diet, mooted by a fellow student at university, which involved subsisting only on the syrupy drink. I have never seen someone expand horizontally so rapidly in such a short period of time. Because this is the one thing that all the diets agree on: in weight loss, sugar is your enemy.
New research – published by online journal Nature Communications, part of the prestigious Nature Publishing Group – this week has found that sugar is not just the enemy of weight loss, but animal (and human) health in general.
"Our results provide evidence that added sugar consumed at concentrations considered safe exerts dramatic adverse impacts on mammalian health," say the researchers, who are based at the University of Utah.
Research in scale
They based their study on the United States's National Research Council recommendation that no more than 25% of a person's consumed calories should be from "added sugar". This meal recommendation was scaled down to mouse proportions and fed to 156 mice.
They found that female mice died at twice the normal rate and males were less likely to reproduce and hold their territory against other males.
"This demonstrates the adverse effects of added sugar at human-relevant levels," said the University of Utah's Wayne Potts, a professor in biology.
He says that in previous studies the mice were fed a disproportionate amount of sugar compared to what humans consume. In this instance, the mice were fed the equivalent of a healthy, sugar-free human diet plus three cooldrinks a day.
The mice were kept in "barns" – a 31m² enclosure – rather than solitary cages, so they could fight over territory and breed naturally. This system for toxicity testing was developed at the University of Utah.
Potts said that the more realistic environment made the test conditions more sensitive as it would reveal subtle toxic effects through how the mice reproduced and fought over territory.
The study found that after 32 weeks "35% of the females fed extra sugar died, twice the 17% death rate for female control mice", the university said. There was no difference in the death rate of male mice, but "males on the added sugar diet produced 25% fewer offspring than control males".
Mice vs humans
Another author on the study, James Ruff, said the sensitive test showed that "the levels of sugar that people typically consume – and are considered safe by regulatory agencies – impair the health of mice."
Priya Seetal, senior dietician at the Sugar Association of South Africa, said: "It seems as though the mice were fed excessive amounts of sugar – over and above what is normally consumed by the human population. Any food eaten in excess will have a negative effect.
"Sugar can be enjoyed in moderation, without negative effects."
She also pointed out that the study was done on mice and not humans.
"Scientists generally agree that mice and humans do not respond the same during an experiment.
"Therefore results obtained from an experiment done on mice do not automatically mean that the same result will be obtained in humans."