Roundup: Long-Term Benefits of ‘Intensive Behavioral’ Weight Loss Programs; Role of Genetics in Substance Use Disorders; and More News

New Review Focuses on Long-Term Effects of ‘Intensive Behavioral’ Weight-Loss Programs in Lowering Risk for Heart Disease, Diabetes

Losing weight through an "intensive behavioral” weight-loss program -- referring to clinical treatment for obesity that focuses on dietary and exercise habits -- was associated with a decrease in risk factors for cardiovascular disease and type 2 diabetes for at least five years — even if some weight was regained, states a new study published in Circulation: Cardiovascular Quality and Outcomes, a peer-reviewed American Heart Association journal.

Regaining some weight is common after behavioral weight loss programs, researchers point out. Some observational studies suggest this weight change pattern of weight loss followed by weight regain may increase cardiovascular risk. However, data from long-term follow-up studies is lacking, states a news release by the American Heart Association.

In the new study, researchers merged the results of 124 studies, representing more than 50,000 participants, with an average follow-up of 28 months. They used the combined results to estimate changes in risk factors for cardiovascular disease and type 2 diabetes after weight loss.

Compared to those in a less intensive program and those in no weight loss program, participants who lost weight through an intensive weight loss program had lower risk factors for cardiovascular disease and type 2 diabetes, said the AHA. These lower risk factors lasted for at least five years after the weight loss program ended.

The decreased risk of being diagnosed with cardiovascular disease or type 2 diabetes also appeared to remain lower even after weight regain. However, few studies followed people for more than 5 years and “more information is needed to confirm whether this potential benefit persists,” said study co-senior author Susan A. Jebb, Ph.D., a professor of diet and population health at the University of Oxford in the United Kingdom, in a statement. “Our findings should provide reassurance that weight loss programs are effective in controlling cardiovascular risk factors and very likely to reduce the incidence of cardiovascular disease,” she said.

Evidence continues to mount that cardiovascular health is improved by following the American Heart Association’s Life’s Essential 8 health metrics: eating healthy food, being physically active, not smoking, getting enough sleep, maintaining a healthy weight, and controlling cholesterol, blood sugar and blood pressure levels.

Shared ‘Genetic Markers’ Linked to Substance Use Disorders in Landmark, NIH-Supported Study

Is it likely that genetics play a role in someone become addicted to alcohol, tobacco, opioids or other drugs? New research considered to be a breakthrough has identified genes commonly inherited across addiction disorders, regardless of the substance being used, states the National Institutes of Health (NIH), which supported the study published in Nature Mental Health.

The research, led by Washington University School of Medicine in St. Louis, “eventually could lead to universal therapies to treat multiple substance use disorders and potentially help people diagnosed with more than one,” states the Washington University School of Medicine in a news release.

The findings are based on an analysis of genomic data from more than 1.1 million people of mostly European ancestry and a smaller population of people of African ancestry.

“There is a tremendous need for treatments that target addiction generally, given patterns of the use of multiple substances, lifetime substance use, and severity seen in the clinic,” said lead author Alexander Hatoum, Ph.D., a research assistant professor of psychological & brain sciences in Arts & Sciences at Washington University. “Our study opens the door to identifying medications that may be leveraged to treat addiction broadly, which may be especially useful for treating more severe forms, including addiction to multiple substances.”

The available data on substance use disorders are very concerning, states the NIH. In 2021, more than 46 million people in the U.S. aged 12 or older had at least one substance use disorder, and only 6 percent had received treatment. About 107,000 people died of drug overdoses in 2021, and 37 percent of these deaths involved simultaneous exposure to both opioids and stimulant drugs. “Drug use and addiction represent a public health crisis, characterized by high social, emotional, and financial costs to families, communities, and society,” states the NIH in a news release.

Previous clinical trials and behavioral studies have focused on individual substances, rather than addiction more broadly.

“Our hope with genomic studies is to further illuminate factors that may protect or predispose a person to substance use disorders—knowledge that can be used to expand preventative services and empower individuals to make informed decisions about drug use,” said Nora Volkow, M.D., director of the National Institute on Drug Abuse (NIDA), part of the NIH.

Even Small Amounts of High-Fat, High-Sugar Foods can ‘Rewire’ Brain, Researcher Say

Eat fatty or sugary foods can fuel a person’s future cravings by activating “the dopaminergic system, the region in the brain responsible for motivation and reward,” states a new study from researchers at Yale University and the Max Planck Institute for Metabolism Research in Germany.

Published in the journal Cell Metabolism, the study monitored a group of volunteers who consumed high-fat, high-sugar yogurt twice per day for eight weeks, in addition to their normal diet. The other group received low-fat, low-sugar yogurt that contained the same number of calories. The brain activity of everyone in both groups was measured before and during the eight weeks.

The volunteers were “healthy, normal-weight participants (who) underwent baseline assessment after initial screening,” the study states.

"Our measurements of brain activity showed that the brain rewires itself…” explains Marc Tittgemeyer, Ph.D., professor at the Max Planck Institute for Metabolism Research, who led the study, in a statement. “It subconsciously learns to prefer rewarding food. Through these changes in the brain, we will unconsciously always prefer the foods that contain a lot of fat and sugar."

The study participants did not gain more weight than the participants in the control group, and their blood sugar and cholesterol levels did not change either. 

The study participants also underwent MRI scans while drinking milkshakes. The scans showed that the milkshakes increased brain activity in the group that had eaten the high-fat, high-sugar yogurt, but not in the control group.

“The current study demonstrates that short-term daily consumption of a high-fat/high-sugar snack decreases preference for a low-fat food,” the study states. “Although the underlying mechanisms remain unknown, these findings demonstrate that, like addictive drugs, habitual exposure to high-fat/high sugar food is a critical driver of neuro-behavioral adaptations that may increase the risk for subsequent overeating and weight gain …”