L-Carnitine

What It Is:
A compound transporting fatty acids into mitochondria for energy production.

What It’s Used For:

• Fat-metabolism support

• May improve endurance in deficient or older users

Typical Dose:

• 1–3 g daily; taken with carbs to aid uptake

Side Effects:

• Fishy odour in sweat/urine at high doses; mild stomach upset possible

Why It’s Rated 1.5/5:
Mechanistically solid, but human studies show minimal fat-loss or performance benefit for healthy adults.