Evidence Review

Review the evidence behind popular ingredients, supplements, devices, and emerging hair-loss claims, with practical limits and safety context.

Strands of dark hair beside a dried autumn leaf on a pale surface, representing seasonal hair shedding

8 min read

Seasonal Hair Shedding: Why Autumn Sheds More, and How to Tell It From Balding

Human hair sheds on a seasonal rhythm that peaks in autumn. Here is how to tell a shed that resolves from pattern loss that does not, and what to measure.

A ceramic tint bowl and tinting brush on a grey surface beside a folded towel, representing hair colouring

8 min read

Does Hair Dye or Bleach Cause Hair Loss? Breakage vs Shedding

Bleach damages the hair shaft but does not reach the follicle. Here is how to tell breakage from shedding by eye, and when dye genuinely causes hair loss.

Sugar cubes beside a glass of water representing diet and hair loss tracking

7 min read

Sugar, a High-Glycemic Diet, and Hair Loss: What the Evidence Says

No good evidence says sugar directly causes baldness. Learn the insulin resistance association, when diet can trigger shedding, and what to track.

An amber dropper bottle beside a leaf representing niacinamide serum for hair and scalp

5 min read

Niacinamide for Hair Loss: What the Evidence Actually Shows

Review the limited human evidence for niacinamide and hair loss, its plausible scalp benefits, where it may fit, and how to track any change.

Quiet still life with a cup of green tea evoking evidence review of EGCG for hair loss

5 min read

Green Tea and EGCG for Hair Loss: Evidence

Green tea and EGCG have interesting laboratory data but limited human hair-growth evidence. Review the studies, safety questions, and tracking limits.

Vitamin D softgels on a sunlit wooden table representing vitamin D supplementation for hair health

5 min read

Vitamin D and Hair Loss: What the Evidence Shows

Review the evidence linking vitamin D and hair loss, when testing may be appropriate, why self-dosing can be risky, and how to track recovery.

Biotin capsule on a lab requisition slip representing biotin supplementation and lab test interference

5 min read

Biotin for Hair Loss: Evidence and Myths

Biotin evidence is weak without a deficiency, and high doses can disrupt lab tests. Learn what research supports and what to discuss before use.

Castor oil bottle and hair loss evidence review

5 min read

Castor Oil for Hair Loss: Evidence Review

Castor oil lacks clinical evidence for hair regrowth. Learn what it may do for the hair shaft, what it cannot treat, and how to evaluate claims safely.

Hair dryer and flat iron heat styling effects on hair loss

7 min read

Heat Styling and Hair Loss: What It Causes

Heat styling can damage hair shafts and make thinning look worse without causing pattern baldness. Learn damage signs, safer habits, and what to track.