Limited evidenceGeneral health

Energy Support Formulas

B vitamins plus adaptogens such as rhodiola, ginseng or ashwagandha, sold for daily energy. B vitamins only restore energy if you are deficient, and the adaptogen trials are small and inconsistent — most of the felt effect in these products comes from caffeine when it is present.

Evidence last reviewed: August 2026

What the science says

B vitamins and subjective energy Limited evidence
A randomised trial of a B vitamin complex with vitamin C and minerals in healthy adults reported improvements in subjective mood and mental tiredness during demanding tasks, and a randomised double-blind trial found reduced fatigue markers with B complex in healthy participants. Both are small, and B vitamins carry no energy themselves — they act as cofactors, so extra intake helps mainly when status is low.
Rhodiola for fatigue Limited evidence
A systematic review of Rhodiola rosea for physical and mental fatigue found a small number of trials with methodological problems and inconsistent results, and concluded the evidence was inconclusive. Individual positive trials exist but have not been reliably replicated.
Blends as sold Limited evidence
No randomised trial has tested the specific multi-ingredient energy blends on the market. Doses of individual actives in these products are often below those used in the trials that generated the claims.

Dosage & safety

Studied doseB vitamins are usually at or well above 100% of the reference intake, with adaptogen extracts at 100–600 mg. Rhodiola trials generally used 200–600 mg/day of extract standardised to rosavins and salidroside.

SafetyHigh-dose B6 taken chronically (above roughly 50 mg/day for long periods) can cause peripheral neuropathy, which is the most common real harm from these products. Niacin causes flushing; B2 turns urine bright yellow, which is harmless. Rhodiola and ginseng can cause agitation and insomnia and may interact with antidepressants and stimulants. Persistent fatigue deserves investigation — anaemia, thyroid disease, sleep apnoea and depression are common causes that a supplement will not fix.

Scientific references

Vitamins and psychological functioning: a mobile phone assessment of the effects of a B vitamin complex, vitamin C and minerals on cognitive performance and subjective mood and energy
Kennedy DO, Veasey RC, Watson AW — Hum Psychopharmacol, 2011
A functional evaluation of anti-fatigue and exercise performance improvement following vitamin B complex supplementation in healthy humans, a randomized double-blind trial
Lee MC, Hsu YJ, Shen SY — Int J Med Sci, 2023
Rhodiola rosea for physical and mental fatigue: a systematic review
Ishaque S, Shamseer L, Bukutu C — BMC Complement Altern Med, 2012

Where to buy

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