Let's be honest: "metabolism boosters" are one of the most overhyped supplement categories. A few things work marginally. Nothing works dramatically. Building muscle is more effective than any pill.
What Actually Has Evidence
Caffeine - Increases metabolic rate 3-11% - Effect is temporary (tolerance builds) - About 100-400mg - Most effective for exercise performance
Green tea extract (EGCG) - Small effect, inconsistent results - Caffeine content may explain most benefit - High doses carry liver risk
Capsaicin (from hot peppers) - Very small metabolic boost - More hype than substance - May reduce appetite slightly
Supporting Thyroid Function
Your thyroid controls metabolism. If it's sluggish, these may help:
Iodine - Only if deficient Selenium - Needed for thyroid hormone conversion Zinc - Supports thyroid function
But: These only help if you have a thyroid issue. They don't "boost" normal thyroid function.
Warning: Don't take thyroid support supplements without checking thyroid levels first. You could make things worse.
The Reality Check
Most "metabolism boosters" are marketing.
Things that actually affect metabolism more than supplements:
- Muscle mass - Muscle burns more calories than fat at rest - Protein intake - Higher thermic effect of food - Sleep - Poor sleep tanks metabolism - Movement - Both exercise and daily activity - Not crash dieting - Severe restriction slows metabolism
A supplement that "boosts metabolism 5%" = maybe 50-100 extra calories burned. That's a small apple. Don't expect miracles.
What to Skip
Raspberry ketones - No human evidence
Garcinia cambogia - Studies don't support weight loss claims
Most "fat burners" - Unproven blends with possible side effects
HCG - Dangerous and ineffective
Anything with "proprietary blend" - Hiding what's actually in it