Vitamin B3 500mg

With B3, the number on the front of the pack tells you what kind of product you're holding. These are the questions our naturopaths ask in store.

A good fit if

• Your diet is light on chicken, fish, peanuts and mushrooms, where most dietary niacin comes from
• You're topping up near the reference intake, usually with a B complex or multivitamin
• You want the form that doesn't cause a flush, and you know to check the active named on the label
• You'd rather start with food. 100 g of chicken breast has about 11 mg

Check with us first if

• You take a statin. Adding gram doses of niacin didn't reduce heart events in either large trial, and the HPS2-THRIVE trial recorded significantly more serious side effects.
• You've got a 500 mg or 1,000 mg tablet. That's tens of times the daily reference intake, so it's worth a chat.
• High cholesterol is why you're shopping. That's one for your doctor, and current evidence doesn't support adding niacin to statin treatment.
• You take prescription medicines. Check with your doctor, pharmacist or our naturopaths before you start.

• Nicotinic acid (niacin). Best known for: The flushing form, and the one with the history in blood fat research. Absorption: Well absorbed by mouth. The flush and the effects at gram doses belong to this form, not the other one. Typical use: Capped at 100 mg per tablet or capsule in a listed medicine. Gram doses added to statin treatment didn't reduce heart and blood vessel events, and HPS2-THRIVE, which tested niacin with laropiprant, recorded significantly more serious side effects.
• Nicotinamide (niacinamide). Best known for: The form that doesn't cause flushing at any dose studied, and doesn't change blood fats. Absorption: Well absorbed by mouth, and it doesn't use the pathway that causes the flush. Typical use: The active in most higher-strength Australian B3 tablets, and the form studied for skin health. That trial used doses far above nutrient level, in people under specialist care, and the benefit stopped when the tablets did.
• Inositol hexanicotinate ("no-flush niacin"). Best known for: Six nicotinic acid molecules bound to inositol, sold as niacin without the flush. Absorption: Not well understood. When commercial products were analysed, several released almost no free nicotinic acid. Typical use: Not in Schedule 1 under its own name, so it can't be a listed medicine's active. Don't confuse it with plain inositol, item 2700, which is allowed.

Reference values. Australia's Nutrient Reference Values set 16 mg a day for adult men and 14 mg for women, as niacin equivalents, where 60 mg of tryptophan counts as 1 mg of niacin. It's 18 mg in pregnancy and 17 mg while breastfeeding. Children need from 6 mg at ages 1 to 3 up to 12 mg at 9 to 13.

Typical supplemental range. Australian B3 tablets are commonly 500 mg or 1,000 mg, which is 30 to 70 times the reference intake. Those are medicine-level doses rather than nutrient top-ups, so talk them through with a practitioner. A B complex or multivitamin sits much closer to the RDI. The blood fat trials used 1,500 to 3,000 mg a day of nicotinic acid, and the skin trial used 1,000 mg a day of nicotinamide.

Upper level. There are two upper limits, depending on the form. For nicotinic acid from supplements and fortified food only, it's 35 mg a day for adults, 30 mg at 14 to 18, 20 mg at 9 to 13, 15 mg at 4 to 8, and 10 mg at 1 to 3. For nicotinamide from all sources, it's 900 mg a day for adults, and 150 to 750 mg for children and teenagers. In pregnancy and breastfeeding, the nicotinamide upper limit hasn't been set, and the guidance says your intake should come from food only.

Worth knowing. A listed medicine can contain no more than 100 mg of nicotinic acid per tablet or dose, so a 500 mg or 1,000 mg B3 tablet will name nicotinamide as its active. It's worth checking the label. What you need depends on your age, diet and health, so talk to one of our naturopaths.

Food first, where the diet allows it.

• Peanuts, roasted, 100 g: 18 mg
• Chicken breast, 100 g: 11 mg
• Sunflower seeds, 100 g: 10.75 mg
• Mushrooms, fresh, 100 g: 3.55 mg
• Potato, peeled, 100 g: 1.73 mg

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

• You take a statin. Adding gram-dose niacin gave no benefit in AIM-HIGH or HPS2-THRIVE, and there were significantly more serious side effects in HPS2-THRIVE.
• You're pregnant. No upper level has been set for nicotinamide; the reference values say food only.
• You're breastfeeding. Same position, same source.
• Children. The nicotinic acid upper level starts at 10 mg a day for ages 1 to 3, far below the strength of a retail B3 tablet.
• You'd take 500 mg or 1,000 mg a day. That's a medicine-level dose, not a nutrient dose.
• You take prescription medicine. Talk to a doctor or pharmacist before taking gram-dose niacin.
• You're looking at no-flush niacin. It's a different substance, and not an allowed active in an Australian listed medicine.
• If you take prescription medicines, check with your doctor, pharmacist or our naturopaths before starting.