Most people can get the vitamin B12 they need from a varied diet that includes animal foods, so a B12 supplement mainly suits vegans, many older adults and people whose medicines or gut conditions reduce absorption. Adults in Australia need just 2.4 mcg a day (NHMRC), and the Australian Dietary Guidelines advise people on a vegan diet to take a B12 supplement (healthdirect). Below: who may be low, how much vitamin B12 per day, forms such as methylcobalamin, B complex benefits and safety, and the signs that mean it is time to see your GP. A supplement cannot diagnose or rule out a deficiency, and neither can this guide.
Vitamin B12 benefits: what it does and what it will not do
Vitamin B12 helps make red blood cells, keeps your nervous system healthy, helps release energy from food and helps your body use folate (healthdirect). Unlike other B vitamins, it is stored in the liver for years, so a low intake can take a long time to show up.
The main B12 supplement benefits are for people who are low or at risk. If your levels are fine, extra B12 is unlikely to add energy or performance: the NIH says B12 supplements do not appear to improve athletic performance or endurance without a deficiency. So does vitamin B12 work? Yes, when it fills a real gap.
How much vitamin B12 per day?
| Group (NHMRC) | Recommended daily intake |
|---|---|
| Adults 19 and over | 2.4 mcg |
| Pregnancy | 2.6 mcg |
| Breastfeeding | 2.8 mcg |
| Upper level | Not set (insufficient data) |
Supplements often contain 500 to 5,000 mcg, which looks huge next to 2.4 mcg. The reason is absorption. The NIH says only about 2% of a 500 mcg dose and 1.3% of a 1,000 mcg dose is absorbed, because the protein that carries B12 from the gut (intrinsic factor) is saturated at 1 to 2 mcg. So a 500 mcg tablet gives roughly 10 mcg that your body actually takes in.
Who may be low in B12?
B12 deficiency is the most common B vitamin deficiency in Australia (healthdirect). You are at higher risk if you:
- follow a vegan or vegetarian diet
- are an older adult, as many have low stomach acid, which reduces B12 absorption from food (NHMRC)
- have pernicious anaemia
- take metformin or a proton pump inhibitor
- have had bariatric surgery, or have a gut condition such as coeliac or Crohn's disease
B12 for vegans. B12 is naturally found only in animal foods (NIH ODS), and the NHMRC says strict vegans will need supplementation. healthdirect lists fortified plant milks, some fortified meat substitutes and some breakfast cereals as the only reliable vegan food sources. A daily B12 supplement, or a multivitamin with B12, is the simple fix. For the protein side, see our best vegan protein powder guide.
Vitamin B12 for women. Women need the same 2.4 mcg as men, rising to 2.6 mcg in pregnancy and 2.8 mcg when breastfeeding. The NHMRC says vegan mothers will need supplementation throughout pregnancy and breastfeeding, and the NIH notes that breastfed babies of mothers who eat no animal foods can have very limited B12 reserves. If you are planning a pregnancy, see your GP, who will also talk about folic acid.
B12 deficiency symptoms: signs to see a GP about
healthdirect lists these common symptoms of B12 deficiency:
- fatigue and weakness
- anaemia
- numbness or tingling in the hands and feet
- memory problems or balance difficulties
These signs have many possible causes, so do not guess. The NIH notes nerve symptoms can appear without anaemia, and healthdirect warns that a deficiency left unchecked can cause permanent nerve damage. See your GP, who may arrange blood tests. If you are low, your doctor may give B12 as tablets, liquid, a nasal spray or injections, and check again after about 3 months (healthdirect).
How to take vitamin B12: forms, lozenges and timing
- Methylcobalamin vs cyanocobalamin: cyanocobalamin is the most common supplement form, and others include methylcobalamin, adenosylcobalamin and hydroxocobalamin. The NIH says no evidence shows absorption differs by form, so choose on format, diet (for example vegan capsules) and value.
- Lozenges vs capsules: the NIH says evidence suggests no difference in effect between forms dissolved under the tongue and forms you swallow. Pick the one you will take.
- When to take vitamin B12: neither healthdirect nor the NIH names a best time of day, so take it at a time you will remember, such as with breakfast. Follow your label: Life Extension's B12 lozenge, for example, can be taken with or without food.
- Medicines: metformin, proton pump inhibitors and H2 blockers can reduce B12 absorption (NIH ODS). If you take them, ask your GP whether your levels should be checked.
Vitamin B complex benefits, and the B6 catch
A B complex combines the eight B vitamins, which help your body release energy from food, keep your nervous system healthy and make red blood cells (healthdirect). Most people get enough from a varied diet, so the main benefit is for people with a restricted diet or a need their GP has identified. healthdirect also says not to double up: if you take a multivitamin, check it before adding a B complex.
The catch is vitamin B6. Its upper level is 50 mg a day, and the TGA warns that B6 can cause peripheral neuropathy, with tingling, burning or numbness, usually in the hands or feet. The TGA says the risk cannot be excluded at doses below 50 mg a day. Products with more than 10 mg a day already carry a warning, and from 1 June 2027 oral products with more than 50 mg and up to 200 mg per daily dose become Pharmacist Only Medicines. Many B complex products contain 50 to 100 mg of B6 per serve, and B6 also turns up in multivitamins, magnesium and zinc products. If you notice tingling or numbness, stop and see your doctor.
Vitamin B12 side effects: is vitamin B12 safe?
For most people, yes. No upper level is set for B12 in Australia because there are insufficient data (NHMRC), and the NIH says it is generally considered safe, even at high doses. If a B product does cause problems, look at the other ingredients: high-dose B6, or niacin as nicotinic acid, which has an upper limit of 35 mg a day and in excess can cause skin flushing, burning, tingling and itching (healthdirect). B vitamin supplements can also interact with some medicines, so check with your doctor or pharmacist (healthdirect).
Products to look at
Labels checked in October 2026. All are in stock online at the time of writing.
- Life Extension Vitamin B12 Methylcobalamin: 500 mcg methylcobalamin per vegetarian lozenge.
- NOW Foods B-12 lozenges: three forms of B12 including methylcobalamin, vegan, one lozenge a day.
- Doctor's Best Fully Active B12: 1,500 mcg methylcobalamin per veggie capsule.
- Doctor's Best Fully Active B Complex: all eight B vitamins plus vitamin C, with 1,000 mcg methylcobalamin and 50 mg B6 in one daily capsule. That B6 dose sits at the upper level, so do not stack it with other B6 products.
- Condemned Labz Multi: 205 mcg methylcobalamin per 2-tablet serve, if you would rather cover B12 with a multivitamin.
Compare more in our best multivitamins guide, or browse vitamins and minerals and vegan supplements. Meat eaters curious about a food-based B12 source can read our beef liver guide.
FAQs
What is the best vitamin B12 supplement in Australia?
The best B12 supplement for you is one that suits your diet and that you will take every day. The NIH says absorption does not differ by form, so methylcobalamin and cyanocobalamin both work, and lozenges work as well as capsules. Vegans should check the capsule and other ingredients are plant-based. If you take a multivitamin, check its B12 first, and see your GP if you have symptoms.
Where can I buy vitamin B12 online in Australia?
You can buy vitamin B12 and B complex supplements online at Supps247, with Australia-wide delivery that usually takes 2 to 8 business days and free shipping on orders of $99.99 or more. You can also visit one of our 18 stores in Victoria and Queensland to compare labels with our team. Stock varies by store, so check the product page before you travel.
When is the best time to take vitamin B12?
Neither healthdirect nor the NIH names a best time of day, so take it when you will remember, such as with breakfast. Labels vary, so follow yours: Life Extension's methylcobalamin lozenge can be taken with or without food. Taking it every day matters more than the timing, especially if you are vegan and rely on a supplement for all your B12.
Do vegans need a B12 supplement?
Yes. B12 is naturally found only in animal foods, and the NHMRC says strict vegans will need supplementation. The Australian Dietary Guidelines, as summarised by healthdirect, advise people on a vegan diet to take a B12 supplement, with fortified plant milks, some meat substitutes and some cereals as the only reliable vegan food sources. Vegan mothers need B12 throughout pregnancy and breastfeeding.
Does vitamin B12 give you more energy?
Only if you are low. B12 helps release energy from food, and fatigue is a common sign of deficiency, so correcting a deficiency can help. But the NIH says B12 supplements do not appear to improve performance or endurance in people who are not deficient. If you are always tired, see your GP for a check-up rather than relying on a supplement.
What are the side effects of vitamin B12 supplements?
Vitamin B12 is generally considered safe, even at high doses, and no upper level is set in Australia. Problems are more likely to come from other ingredients, such as high-dose vitamin B6 in some B complex products, which can cause tingling, burning or numbness in the hands or feet. Stop and see your doctor if that happens, and check medicine interactions with a pharmacist.
Sources: NHMRC Nutrient Reference Values, vitamin B12; NIH Office of Dietary Supplements, vitamin B12 fact sheet; healthdirect, vitamin B deficiency; healthdirect, vitamin B and your health; TGA, medicines containing vitamin B6.
Order online with Australia-wide delivery, free on orders of $99.99 or more, or visit a Supps247 store in Melbourne, regional Victoria or Brisbane to compare products in person before you buy. Members can use our member price match on full-priced items.
Always read the label and follow the directions for use. If you have a medical condition, are pregnant or take regular medication, check with your doctor first.
