Wearables Don’t Move the Health Needle

Systematic reviews show that consumer wearables produce at best small and often fragile increases in physical activity, and effect sizes shrink further after correcting for publication bias. For serious clinical detection (e.g., atrial fibrillation) some devices can help, but for everyday behavior change the evidence is weak and overstated. — If true, policymakers, employers, insurers, and consumers should reconsider investments, incentives, and privacy trade‑offs tied to mass wearable deployment.