Cochrane Review Deflates Intermittent Fasting Hype as Sugary Drinks Linked to Teen Anxiety

A systematic review and meta-analysis from Bournemouth University, published in the Journal of Human Nutrition and Dietetics, found a consistent association between high sugar-sweetened beverage consumption and anxiety symptoms in teenagers. Pooling findings from multiple earlier studies, the team found that higher intake of sugary drinks — including sodas, energy drinks, sweetened juices, flavored milks, and sweetened teas — was associated with a 34% increased risk of anxiety symptoms in young people.

The research arrives amid growing concern about adolescent mental health: an estimated one in five children and adolescents globally lived with a mental health disorder as of 2023, with anxiety among the most commonly reported. Study co-author Dr. Chloe Casey noted that public health campaigns have traditionally focused on the physical consequences of poor diet, such as obesity and type 2 diabetes, while the mental health implications of diet have been underexplored by comparison, particularly for drinks that are energy dense but low in nutrients.

The researchers were careful to stress that the study cannot establish causation. Because the analysis relied on pre-existing survey data, it remains possible that teens already experiencing anxiety consume more sugary beverages as a coping mechanism, or that shared factors such as sleep disorders or family circumstances drive both behaviors simultaneously. The authors describe the findings as identifying an unhealthy connection that warrants further, more rigorous investigation before any causal conclusions can be drawn.

A landmark study published in JACC, the flagship journal of the American College of Cardiology, has reframed decades of dietary debate by showing that food quality — not macronutrient ratio — is the more critical factor for protecting heart health. Researchers at the Harvard T.H. Chan School of Public Health analyzed data from 198,473 U.S. adults across three major long-running cohort studies, the Nurses Health Study, NHSII, and the Health Professionals Follow-up Study, with over 30 years of follow-up.

Both low-carbohydrate and low-fat dietary patterns were linked to a lower risk of coronary heart disease when they emphasized nutrient-dense, plant-forward foods such as whole grains, legumes, and healthy unsaturated fats. In contrast, versions of these same diets built around refined carbohydrates, processed foods, and animal products were associated with higher coronary heart disease risk and unfavorable metabolic markers — including elevated triglycerides and inflammatory proteins. Metabolomic analysis revealed favorable biological changes in those following higher-quality diet versions.

Researchers concluded that public messaging centered on diet labels such as low-carb or low-fat may be less useful than guidance emphasizing whole, minimally processed foods regardless of macronutrient composition. The results were published February 11, 2026 in JACC and represent one of the most comprehensive investigations of diet quality, metabolomic profiles, and coronary heart disease risk conducted to date.