Weekend binge undoes a week’s good eating, and why US meals out are gutbusting

Microbes in the guts of rats fed a healthy diet for four days a week and junk for three days were almost the same as those fed entirely on junk, study finds; another shows nearly all US restaurant meals have too many calories

PUBLISHED : Friday, 22 January, 2016, 7:00am
UPDATED : Friday, 22 January, 2016, 10:10am

If you eat healthily during the week but have cheat days at the weekend and binge on junk food, it’s likely to be just as bad for your gut health as a consistent diet of junk, a new study suggests. Published in the journal Molecular Nutrition and Food Research, researchers at the University of New South Wales in Australia compared the abundance of gut microbiota in rats given continuous access to either a healthy diet or junk food with a group cycled between the two diets, healthy for four days and junk for three, over 16 weeks. At the end of the study, rats on the cycled diet were 18 per cent heavier than those on the healthy diet, while leptin and insulin levels in cycled rats were in between rats fed junk or healthy food. The microbiota of cycled rats was almost indistinguishable from rats fed a constant diet of junk, with both groups’ microbiota significantly different from those in the rats fed a healthy diet. The junk food diet also reduced the abundance of microbial species capable of metabolising flavonoids, which have been suggested to not only assist in weight loss but also exert neuro-protective functions within the brain. Disruption to the gut microbiota has been linked with gastrointestinal conditions such as inflammatory bowel disease and obesity. Cycled rats also showed large swings in food intake, consuming 30 per cent more energy than those maintained on the healthy diet only. When cycled rats switched back to a healthy diet, they consumed half as much food as those maintained on a healthy diet only.

Meals at most US dining establishments tip the scales

Here’s a reason why it’s so hard to eat healthy when eating out: a new study that measured 364 restaurant meals from both large-chain and local restaurants in the US has found that 92 per cent of the meals exceeded recommended calorie requirements for a single meal. In 123 restaurants in three cities – Boston, San Francisco and Little Rock, Arkansas – Tufts University researchers found that a single meal serving, without beverages, appetisers, or desserts sometimes exceeded the caloric requirements for an entire day. The data were collected between 2011 and 2014, and cuisines studied included American, Chinese, Greek, Indian, Italian, Japanese, Mexican, Thai and Vietnamese fare. The study also found that American, Chinese and Italian meals had the highest calorie counts with a mean of 1,495 calories per meal. Study co-author William Masters, a professor of food economics, believes that local ordinances empowering customers to order partial portions at partial prices would lead restaurants to adjust their default sizes towards what the average customer wants, rather than the hungriest person. “Customers could then order anything on the menu in a more appropriate size, and be able to eat out more often without weight gain,” he says.

Anxiety can impact people’s walking direction

People experiencing anxiety and inhibition have more activity in the right side of the brain, causing them to walk in a leftward trajectory, according to new research from the University of Kent. The study set out to establish why individuals display a tendency to allocate attention unequally across space. People were blindfolded and asked to walk in a straight line across a room towards a previously seen target. The researchers found that blindfolded individuals who displayed inhibition or anxiety were prone to walk to the left, indicating greater activation in the right hemisphere of the brain. The findings indicate the brain’s two hemispheres are associated with different motivational systems - the right side to inhibition, and the left to approach. This may have implications for the treatment of unilateral neglect, which is a condition caused by a lack of awareness of one side of space. In particular, individuals suffering from right-sided neglect may benefit from interventions to reduce anxiety.