Cordyceps Benefits: What the Evidence Says, Dosage and Side Effects (UK)

What is cordyceps?

Cordyceps is a group of fungi. The famous wild form, now usually called Ophiocordyceps sinensis, grows on caterpillar larvae high on the Tibetan plateau and is extremely expensive. Almost all supplements are grown in labs instead, either as a fermented mycelium (often sold as “CS-4”) or as cultivated fruiting bodies of Cordyceps militaris. It isn’t psychoactive and has none of the effects of “magic” mushrooms.

The compounds researchers study most are cordycepin and adenosine (both nucleosides), polysaccharides including beta-glucans, and sterols. Cordyceps species infect insects, not people, so the zombie fungus in TV dramas is fiction.

We don’t sell a cordyceps product. If you’re building a mushroom routine, our Reishi Mushroom Adaptogenic Complex is a different mushroom: a reishi hot chocolate made with reishi mushroom, cocoa, maca and coconut milk. It contains a little natural caffeine from the cacao.

Cordyceps sinensis vs militaris

Wild Cordyceps sinensis, now classified as Ophiocordyceps sinensis, is the caterpillar fungus dug up by hand on the Tibetan plateau and in the Himalayas. Demand has made it one of the world’s most valuable biological commodities, and collectors in four countries report harvests falling through overharvesting and a warming climate. Scarcity has also brought counterfeits, so an everyday supplement labelled “Cordyceps sinensis” is almost never the wild mushroom.

Instead, most supplements use one of two lab-grown options. CS-4 is mycelium (the root-like threads) grown by fermentation in tanks; the original CS-4 strain has been identified as a related fungus, Paecilomyces hepiali, and fermented mycelium has a different chemical profile from wild caterpillar fungus. Cordyceps militaris is a separate species whose fruiting bodies (the mushroom itself) are easy to cultivate.

Neither has been shown to be better in head-to-head trials. Here’s what the wording on a label usually means:

• “Cordyceps sinensis” or “CS-4”: almost always fermented mycelium, not the wild fungus.
• “Cordyceps militaris fruiting body”: the cultivated mushroom itself; look for a stated cordycepin figure.
• “Mycelium” or “myceliated grain”: may include the grain it was grown on (see how to choose).
• “Wild” or “Himalayan” caterpillar fungus: very expensive and often faked, so be sceptical of anything cheap.

Could cordyceps infect humans?

No. The fungus in The Last of Us is a fictional, unnamed cordyceps. Its real-life cousins are the “zombie-ant” fungi such as Ophiocordyceps unilateralis, which genuinely do take over carpenter ants: infected ants climb up and clamp their jaws onto a leaf, where they stay fixed long after death. But these fungi are highly specific to their insect hosts, and our body temperature of about 37°C is a strong barrier: when researchers tested about 4,800 fungal strains, most couldn’t grow at mammalian temperatures. Caterpillar fungus mycelium grows best at about 16°C. Supplement cordyceps are different, lab-grown species.

Cordyceps benefits: what the research shows

Most “benefits of cordyceps” lists are built on lab and animal studies. We searched PubMed in October 2026 and read the human trials and reviews behind each popular claim. Here is what they found, with our honest rating of how certain each one is.

Our take: cordyceps may give a small lift to exercise capacity in less-trained or older people, but don’t expect a performance boost if you’re already fit. The immune findings are changes in blood tests, not proof of fewer colds. The kidney and lung studies were in people with diagnosed disease, using cordyceps alongside hospital treatment, mostly in China, so they don’t tell you what a supplement does for a healthy adult. Libido, testosterone, blood sugar and memory claims rest almost entirely on animal and lab work.

If you have kidney disease or a lung condition such as COPD, don’t add cordyceps without talking to your specialist. A placebo-controlled trial of militaris capsules in COPD has been planned, which should give a clearer answer. For a wider view of mushrooms and energy, see adaptogens for energy, and for mood and stress, best mushrooms for anxiety.

Cordyceps for men and women

Cordyceps for men

A lot of cordyceps marketing is aimed at men, mostly around stamina, libido and testosterone. Most of the human trials did recruit men (the Korean immune trial, the cyclists and the reaction-time study), but they measured fitness and blood markers, not hormones or sexual function. The testosterone findings come from mice and cell studies, and the Memorial Sloan Kettering Cancer Center notes that whether this happens in humans is unknown.

There is no special dose for men: the trials above used 1 to 4g a day. If low libido, erection problems or tiredness are bothering you, see your GP rather than self-treating, as these can have medical causes worth checking. Our supplements for men over 40 guide covers what is worth taking.

Cordyceps for women

Here is the honest version. There are no authorised health claims for cordyceps, and few trials have looked at women specifically.

• Exercise and energy: the cyclist and reaction-time studies in our table recruited only men, and the published summaries of the others don’t report results for women separately.
• Immune markers: the Thai trial is one of the few to report women separately. In this small trial, women who had a militaris drink for 8 weeks showed higher natural killer cell activity than at the start, compared with placebo, but it measured blood markers, not colds or infections.
• Tiredness: we found no trial of cordyceps for fatigue in women. If you’re tired all the time, see your GP.
• Fertility, periods and hormones: the claims online rest on cells in a dish, and those point both ways. One study found cordyceps mycelium raised oestradiol production by human ovary cells, while another found cordycepin dampened a key hormone-making protein in the same type of cell. Neither shows what a capsule does in the body, and we found no placebo-controlled trial for menopause, periods or fertility. Our mushrooms for menopause guide covers the animal research.

Don’t take cordyceps if you’re pregnant, trying to conceive or breastfeeding, as its safety isn’t known. We don’t recommend our products during pregnancy or breastfeeding. Avoid it too if you have an autoimmune condition such as lupus or rheumatoid arthritis, or take immunosuppressants, as it may make symptoms flare, and check with your GP or pharmacist if you take a blood thinner, as it may increase bleeding risk.

Cordyceps dosage and how to take it

No official dose has been set for cordyceps. These are the amounts used in the human trials:

• Amount: 1 to 3g a day is typical. Follow the label, as extract strengths vary a lot between products.
• Extract type matters: a gram of concentrated fruiting-body extract isn’t the same as a gram of whole mycelium powder. Compare products by what’s in them (species, part, beta-glucans), not just grams.
• Timing: morning or 30 to 60 minutes before exercise. Many people avoid it late in the day.
• With food: taking it with breakfast can help if it upsets your stomach.
• Formats: capsules, powders stirred into coffee or smoothies, tea or gummies. See mushroom coffee, mushroom tea and our guide to mushroom gummies, which often contain far less mushroom per serving than the trials used.
• Start low: begin at the lower end and check with your GP or pharmacist first if you take any medication.

How long does it take to work?

In the longer trials, changes appeared after 3 to 12 weeks, not after a single dose. If you try it, take it daily for at least four weeks and keep a simple note of your energy and training before deciding whether it’s worth continuing.

Side effects and who should avoid it

Cordyceps is generally well tolerated in short trials, and no serious side effects have been reported in them. It isn’t risk-free, though:

• Common: mild stomach upset, nausea and dry mouth.
• Allergy: hives, rash, itching or swelling are possible. Stop and get medical help if you have any breathing difficulty or swelling of the face or tongue.
• Bleeding: lab studies show cordyceps can affect blood platelets, and there is a case report of heavy bleeding after a tooth extraction. Avoid it if you take blood thinners (such as warfarin, apixaban or clopidogrel) or have a bleeding disorder, unless your doctor agrees.
• Before surgery: stop at least two weeks before planned surgery or dental work, and tell your surgeon or dentist you’ve been taking it.
• Diabetes medicines: it may add to the effect of insulin or tablets that lower blood sugar. Check with your GP or pharmacist first.
• Immunosuppressants and autoimmune conditions: because it may stimulate the immune system, avoid it if you take immunosuppressants (for example after a transplant) or have an autoimmune condition such as rheumatoid arthritis, lupus or MS, unless your specialist agrees.
• Blood cancers: Memorial Sloan Kettering advises people with myeloid-type cancers not to take it, based on animal findings.
• Pregnancy and breastfeeding: avoid, as safety isn’t known.
• Children: not for under-18s. All Evopure products are for adults only.
• Quality: mushrooms can absorb heavy metals from where they grow, so choose a cultivated product tested for contaminants.

How to choose a cordyceps supplement in the UK

Cordyceps is sold in the UK as a food supplement. There are no authorised health claims for it on the GB register, so be wary of labels promising stamina, hormones or immunity. Use this checklist:

• Species named: Cordyceps militaris or Cordyceps sinensis (CS-4). “Cordyceps” on its own isn’t enough.
• Part used: fruiting body, mycelium, or both. Mycelium grown on grain such as oats or rice is often ground up with the grain, which is mostly starch.
• Beta-glucan figure: look for a tested beta-glucan percentage. A “polysaccharides” figure can include starch, and lab methods now measure the two separately.
• Cordycepin: for militaris, a stated cordycepin content makes products easier to compare.
• Dose per serving: check it is in the range used in trials (1 to 3g of mushroom, or a clearly stated extract equivalent).
• Lab testing: third-party certificates for heavy metals and microbes, ideally from an ISO 17025 lab.
• Short ingredients list: watch for added caffeine or stimulants in “energy” blends.

Our best mushroom supplements UK guide explains these label terms in more depth.

Cordyceps vs lion’s mane vs reishi

Full comparison: lion’s mane vs reishi vs cordyceps. For the morning focus mushroom, read our lion’s mane guide, and for all the popular mushrooms, see our adaptogenic mushrooms guide.

We don’t currently sell a cordyceps product. For the evening side of a mushroom routine, our Reishi Mushroom Adaptogenic Complex is a reishi hot chocolate with cacao, maca and coconut milk.

Related guides

• The best supplements for energy and stamina.
• For the evening mushroom, see our reishi mushroom guide.
• How shilajit compares for stamina.
• Rhodiola rosea, the herb often paired with cordyceps in sports blends.
• Which mushrooms have evidence for inflammation.
• Mushrooms for menopause, including the animal studies of cordyceps and menopause weight.
• For a mineral with an authorised testosterone claim, see our guide to zinc for men and testosterone.
• If you’re comparing woody mushrooms too, see chaga: what the research shows and how to make chaga tea.
• Spacegoods, a mushroom coffee that lists Cordyceps sinensis.
• DIRTEA’s cordyceps gummies and the rest of its range.
• Cordyceps sinensis is listed in Ankhway mushroom gummies at 250mg dried-mushroom equivalent per serving.
• Turkey tail is also studied for immune markers; our turkey tail guide explains what the research does and doesn’t show.
• How mushrooms compare with vitamins for the immune system.
• Shiitake is the functional mushroom most people already eat; our shiitake mushroom guide covers its side effects and the evidence.
• For the mushroom people try in the evening rather than the morning, see reishi for sleep.