Which supplements have the strongest research for runners?

Caffeine and carbohydrate fuelling, on the pages we cover. These ratings are proposed until an expert reviewer confirms them. Each page shows the studies behind its rating, distance by distance.

Do runners need to take supplements?

We don't recommend taking any supplement: we report what runners are using and what the research says. Most gains come from consistent training. Talk to your GP or a registered sports dietitian before trying one.

Which supplements are banned in sport?

BPC-157 and TB-500 are prohibited by WADA. Any supplement can be contaminated; each page explains batch testing, which reduces the risk but never removes it.

Which supplements have been studied in marathon runners?

Carbohydrate fuelling has been studied at the marathon distance. The explorer filters every page by the distance it was studied at.

Which supplements have been studied for 5K and shorter races?

Bicarb, caffeine, beta-alanine, beetroot juice and ketone supplements have been studied at 800 m to 5K. Research at one distance doesn't carry over to another, so each page reports them separately.

How are the research ratings decided?

Each page is rated Strong, Emerging, Weak or Banned from the studies it cites, as set out on the methodology page (/blog/supplements/methodology/). These ratings are proposed until an expert reviewer confirms them.

Supplements in running: what's being used and what the research says

We report what runners are using and what the research says. We don't recommend taking any supplement. Talk to your GP or a registered sports dietitian before trying one.

In short

Of the 14 supplements we cover, the research for runners is strongest for caffeine and carbohydrate fuelling (ratings proposed, awaiting expert review). It is emerging for 8 more, including bicarb, electrolytes and beta-alanine. BPC-157 and TB-500 are banned in sport. None replaces consistent training.

supplements: 14
studies tabulated: 180
references cited: 556

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One deep guide per supplement: what it is, the claims checked against the research, what studies found at each race distance, side effects, and where it stands with anti-doping rules. Every claim links to its reference. Ratings are marked as proposed until an expert reviewer confirms them.

Start with your race or your goal

By distance studied

By goal

Every supplement, in brief

Performance

Sodium bicarbonateResearch: Emerging (proposed, awaiting expert review)
A small benefit in short, hard efforts across sports; running-only trials are less clear. Stomach upset is common.
Claims checked 15 studies Anti-doping Quiz
CreatineResearch: Weak (proposed, awaiting expert review)
Strong evidence for strength and repeated sprints; for distance running, trials show no benefit, and loading can add 1 to 2 kg.
Claims checked 15 studies Anti-doping Quiz
CaffeineResearch: Strong (proposed, awaiting expert review)
Longer time to exhaustion and slightly faster time trials in runners; studies mostly used 3 to 6 mg/kg, responses vary and sleep can suffer.
Claims checked 12 studies Anti-doping Quiz
Beta-alanineResearch: Emerging (proposed, awaiting expert review)
A small benefit in hard efforts of about 1 to 4 minutes after weeks of daily use; little evidence for longer races.
Claims checked 13 studies Anti-doping Quiz
Beetroot and nitratesResearch: Emerging (proposed, awaiting expert review)
Longer time to exhaustion in lab tests, but no clear benefit in time trials or in well-trained runners. Can turn urine pink.
Claims checked 14 studies Anti-doping Quiz

Fuelling

Electrolytes and sodiumResearch: Emerging (proposed, awaiting expert review)
Can help replace sweat losses in long, hot events; extra sodium hasn't been shown to prevent cramps or low blood sodium.
Claims checked 13 studies Anti-doping Quiz
Carbohydrate fuellingResearch: Strong (proposed, awaiting expert review)
Carb loading, race-morning meals, gels and drinks, and refuelling: clearest gains in races over about 2 hours, mixed at about an hour. Gut problems are common.
Claims checked 13 studies Anti-doping Quiz

Health and recovery

Vitamin DResearch: Weak (proposed, awaiting expert review)
No running performance gain in trials, even after low levels were corrected. The NHS says everyone should consider one in autumn and winter.
Claims checked 13 studies Anti-doping Quiz
Omega-3Research: Emerging (proposed, awaiting expert review)
No faster times in the one trial we found that timed runners, and an inconsistent effect on soreness after hard exercise.
Claims checked 13 studies Anti-doping Quiz
IronResearch: Emerging (proposed, awaiting expert review)
Gains shown only when iron is low, mostly in women; no benefit when iron is normal. Sports bodies say low iron should be confirmed first.
Claims checked 11 studies Anti-doping Quiz
ProteinResearch: Emerging (proposed, awaiting expert review)
Food usually meets runners' protein needs. Extra protein hasn't clearly improved race performance; recovery and training results are mixed.
Claims checked 12 studies Anti-doping Quiz
CollagenResearch: Emerging (proposed, awaiting expert review)
Two small, industry-part-funded trials found bigger gains in a 1-hour run. Tendon and strength effects alongside training are uncertain.
Claims checked 14 studies Anti-doping Quiz

Hype check

Peptides (BPC-157 and TB-500)Research: Banned (proposed, awaiting expert review)
Prohibited in sport at all times. Most of the research is in animals; there are no controlled trials in athletes.
Claims checked 7 studies Anti-doping Quiz
KetonesResearch: Weak (proposed, awaiting expert review)
No performance benefit in meta-analyses or most running trials, and some trials found slower times. Stomach upset is common.
Claims checked 15 studies Anti-doping Quiz

Research alerts

Put it into your training

Most gains come from consistent training. These are the plans, race guides and tools the research pages link to.

Goal-time plans

Race guides and tools

From the blog

Questions runners ask

Which supplements have the strongest research for runners?: Caffeine and carbohydrate fuelling, on the pages we cover. These ratings are proposed until an expert reviewer confirms them. Each page shows the studies behind its rating, distance by distance.
Do runners need to take supplements?: We don't recommend taking any supplement: we report what runners are using and what the research says. Most gains come from consistent training. Talk to your GP or a registered sports dietitian before trying one.
Which supplements are banned in sport?: BPC-157 and TB-500 are prohibited by WADA. Any supplement can be contaminated; each page explains batch testing, which reduces the risk but never removes it.
Which supplements have been studied in marathon runners?: Carbohydrate fuelling has been studied at the marathon distance. The explorer filters every page by the distance it was studied at.
Which supplements have been studied for 5K and shorter races?: Bicarb, caffeine, beta-alanine, beetroot juice and ketone supplements have been studied at 800 m to 5K. Research at one distance doesn't carry over to another, so each page reports them separately.
How are the research ratings decided?: Each page is rated Strong, Emerging, Weak or Banned from the studies it cites, as set out on the methodology page (/blog/supplements/methodology/). These ratings are proposed until an expert reviewer confirms them.