Activated Charc

With charcoal, the main question isn't how much to take but what else you're taking. These are the questions our naturopaths ask in store before anyone buys it.

A good fit if

• Wind and gas after meals is your reason for looking at it, rather than a cleanse or a whiter smile
• You take no regular medicine, or you can easily keep it hours away from the charcoal
• You want something for a particular meal, a trip or a few days, not a daily habit
• You're comfortable knowing the evidence covers how much gas builds up, not how it smells
• You'd rather know now that your stool will turn black than find out on the day

Check with us first if

• You take any prescription medicine. Charcoal binds medicines in your gut and the Australian label warning says so plainly, so get the timing from your pharmacist, not from a label.
• Your medicine is one where a missed dose matters, such as the contraceptive pill, thyroid medicine, epilepsy medicine, blood thinners (anticoagulants) or immunosuppressants. The binding isn't selective, so none of them are safe from it.
• You're thinking of taking it repeatedly. Repeated doses pull medicine back out of your bloodstream as well as blocking it in your gut, so spacing doses lowers the risk but doesn't remove it.
• It's for a child. The required Australian warning says charcoal should be used with caution in children, because it may interfere with how nutrients are absorbed.
• You're already eating poorly or recovering from illness, since the same pores that take up gas take up nutrients.
• You're buying charcoal as part of a combination product. Everything else in it brings its own cautions, and this page doesn't cover them.
• You take any prescription medicine. Check with your doctor, pharmacist or our naturopaths before starting.

• Capsules and tablets (commonly 250-560 mg each). Best known for: The measured-dose format most people mean by charcoal tablets. Absorption: Nothing is absorbed. Charcoal binds things in the gut and leaves in your stool, so there's no blood level to measure. Typical use: Wind and gas around a meal. Reaching the amount used in the research generally takes several capsules each time.
• Loose powder. Best known for: The simplest way to reach a full gram, and the messiest. Absorption: As above. Typical use: The same job as capsules, if you care more about the dose than the texture. In the tooth-whitening trial, powder scored lowest for ease of use and comfort.
• Coconut shell, hardwood or peat charcoal. Best known for: Source claims on the front of the pack, usually framed as surface area. Absorption: As above. Typical use: No human trial we reviewed compares one source with another, so claims that one source is better are marketing rather than findings.
• Activated bamboo charcoal. Best known for: The only source with a trial of its own. Absorption: As above. Typical use: That trial was a 46-person pilot in stage 3 kidney disease, run under medical supervision, and its authors asked for larger studies. It tells you nothing about a healthy adult buying charcoal for wind.
• Charcoal with simethicone and magnesium oxide. Best known for: The combination behind the one solid indigestion trial. Absorption: As above. Typical use: A 276-person trial found the combination eased indigestion symptoms compared with placebo, but three actives went in, so the result can't be credited to the charcoal.
• Charcoal toothpaste and tooth powder. Best known for: A cosmetic, not a listed medicine. Absorption: Not applicable. Typical use: The evidence goes against the whitening idea. How abrasive they are also varies widely between products, and many charcoal pastes contain no fluoride at all.
• Pharmacy and hospital suspension (50 g and up). Best known for: A completely different kind of product, given by clinicians. Absorption: Timing matters: on average it cut drug absorption by 47.3% at 30 minutes, falling to about 20% by three hours. Typical use: Acute poisoning, under supervision, and not to be given unless the airway is intact or protected. Never something to buy for home and never a reason to buy capsules.

Reference values. There isn't one. Activated charcoal isn't a nutrient, so there's no Australian reference value for it, no deficiency to correct, and nothing on a charcoal label is a percentage of any official figure.

Typical supplemental range. Australian capsules commonly hold 250–560 mg each, and directions vary by brand. The only amount a regulator has reviewed the evidence for is 1 g at least 30 minutes before a meal and 1 g shortly after. That's two grams per meal, which is several capsules for most products. Powder makes it easier to reach that amount than capsules do.

Upper level. None is set. Australia's permitted ingredients list (Schedule 1) sets no maximum daily dose and no limit on how it's taken. What limits it instead is the label warning every product must carry, which says it isn't recommended for long-term use. The 50 g and larger doses you'll read about for poisoning are given in hospital under supervision, and they're no guide to anything sold on a shelf.

Worth knowing. Charcoal binds whatever it meets, so keep it well away from your medicines and, ideally, away from a meal you're relying on for nutrition. What you need depends on your age, diet and health, so talk to one of our naturopaths.

Food first, where the diet allows it.

• No food supplies activated charcoal: it's a manufactured adsorbent rather than a dietary component, so there's no natural intake and no food-based recommendation
• Black ice cream, black buns and black drinks coloured with vegetable carbon: colour-level amounts only. These are foods, they carry no therapeutic claim, and nothing on this page applies to them
• Burnt toast and charred food: not the same thing. Ordinary char has none of the engineered pore structure that makes activated charcoal work

If any of these sound like you, talk to one of our naturopaths or your doctor before you start.

• You take regular prescription medicine. Charcoal binds medicines in the gut, and the mandatory Australian label warning says it may interact with other medicines; ask a pharmacist about timing.
• You'd take it repeatedly or several times a day. Across 21 studies of drugs given intravenously, repeated charcoal doses cut the median half-life by 45.7% and the area under the curve by 47.0%, so spacing doses reduces the interaction without removing it.
• Children. The mandatory Australian label warning says charcoal should be used with caution in children since it may interfere with absorption of nutrients.
• You'd use it long term, at any age. The mandatory Australian label warning says activated charcoal is not recommended for long-term use.
• You're pregnant or breastfeeding. There's no safety or effectiveness information in the evidence we reviewed, so don't take it, and talk to a practitioner.
• You suspect poisoning. This is for clinicians only; charcoal must not be given unless the person's airway is intact or protected, and it isn't something to give at home.
• You use charcoal toothpaste. How abrasive it is varies widely between products and many contain no fluoride, which is a loss rather than a neutral swap.
• If you take prescription medicines, check with your doctor, pharmacist or our naturopaths before starting.