NPR Science Desk Rates Seven Wellness Trends: Creatine Gets High Marks, Methylene Blue Does Not

NPR's science desk reviewed seven wellness trends that gained traction in 2025 and rated each one based on what the research actually shows.

Creatine supplements came out near the top. A review of 35 studies found that combining creatine with resistance training leads to lean muscle gains. Jose Antonio, a professor of exercise science, called the evidence for muscle growth "overwhelming." The caveat: supplements alone are not enough. You still need to exercise.

Continuous glucose monitors for people without diabetes got a mixed review. Some users have lost weight and improved their diets by tracking blood sugar in real time. Others have not seen results. One study found that the same meal eaten on two different days produced very different readings, suggesting the data is not always reliable.

Full-fat dairy got a cautious thumbs-up. A review of the research found that fat-free, low-fat, and full-fat dairy products have similar effects on heart disease risk. Some studies even show benefits from higher-fat dairy. Experts say worrying about fat content in dairy is largely a distraction from bigger dietary concerns like excess sugar and refined carbs.

Weighted vests for daily walks got a lukewarm assessment. Evidence that they build bone density is thin. They may offer some cardiovascular benefit and burn more calories, but resistance training is a better option for building muscle and bone.

Methylene blue dye, promoted by wellness influencers as an anti-aging supplement, did not fare well. Rodent studies show some benefits, but human studies have not shown significant effects in healthy people. There are also risks, including serotonin toxicity.

High-protein packaged snacks got a skeptical rating. Many products make "high protein" claims without meeting meaningful thresholds. Even when the protein content is real, the snacks are often still high in calories, sugar, or processed ingredients.

Beef tallow for cooking and skincare also received a cautious response. Nutrition scientists note that saturated fats can contribute to cardiovascular problems, and tallow-based skincare products may worsen acne for some users.