Eating Sugar Makes Men Sad but Not Women, 30-Year Study Indicates

Bags of granulated sugar move along the production line at a Tate & Lyle refinery in East London on October 10, 2016. REUTERS/Peter Nicholls

A new study indicates that men may want to monitor sugar in their diets a little closer.

Researchers have linked higher sugar intake to an increased likelihood of mental health problems in men more than women in a study spanning more than 30 years newly published in Scientific Reports. Skeptics have pointed to some flaws, however, and questions still remain.

The University College of London's Whitehall II study, which started in 1985, enrolled more than 10,000 British civil servants aged 35 to 55. The study monitored health and behavior over many years, conducting surveys with each participant each over 10 phases three years apart. More men, nearly 66.9 percent, participated compared with 33.1 percent women.

At the third, fifth, seventh and ninth phases of the study, the participants' diets were surveyed, including 15 kinds of food placed in the "sweet food and beverage" category like cakes, cookies, sugar placed into coffees or teas and soda.

The researchers then compared the food intake surveys with a general health questionnaire, which attempts to measure symptoms of depression or other common mental disorders (CMDs), such as anxiety and insomnia.

"The present long-term prospective study is the first to investigate the association of sugar consumption from sweet food/beverages with prevalent, incident and recurrent mood disorders, while also examining the effect these disorders might have on subsequent sugar intake," the study reads.

It goes on: "Further, we found an increased likelihood for incident CMD in men and some evidence of recurrent depression in both sexes with higher intakes of sugar from sweet food/beverages."

In addition to sugar intake, the study also looked to factors such as marital status, age, ethnicity and if the participant smoked to see if there was another underlying reason for depression.

Women under age 50 were far more likely to have depression or other CMD at the start of the study compared to the men. In particular, those who were divorced or widowed, smoked and got less sleep had a higher prevalence of these conditions. But across the duration of the study, the researchers found no associations between depression and sugar intake among women.

However, among the men who did have depression, the researchers found that their mental state was tied to consumption of sweet food and drinks. Men who reported a CMD over a five-year period showed a particularly tight link to sugar.

Critics of the study point out that the researchers did not include natural sugars that are found in foods like milk or drinks like alcohol when considering intake, highlighting one of the common problems in nutritional studies.

"The dietary analysis makes it impossible to justify the bold claims made by the researchers about sugar and depression in men," a spokeswoman for the British Dietetic Association, Catherine Collins, said according to AFP.

"Reducing intake of free sugars is good for your teeth, and may be good for your weight, too. But as protection against depression? It's not proven."