B Complex Liquid

A serving of this liquid is half a teaspoon, 2.5 ml, once a day. Mix it into about 200 ml of water with breakfast, as the label directs. That serving provides thiamin 10.2 mg, riboflavin 10.4 mg as riboflavin 5-phosphate, niacin 25 mg, vitamin B6 10.7 mg as pyridoxal 5-phosphate, folate 400 mcg as methylfolate, vitamin B12 500 mcg as methylcobalamin and adenosylcobalamin, biotin 100 mcg, pantothenic acid 25.5 mg and choline 83.3 mg. A 100 ml bottle holds 40 servings. The ingredients are purified water, choline chloride, dexpanthenol, niacinamide, pyridoxal 5-phosphate, riboflavin 5-phosphate, potassium carbonate, thiamine HCl, citric acid, calcium L-methylfolate, adenosylcobalamin, methylcobalamin and biotin.

Sources: Product label.

An active B complex supplies the B vitamins in the forms the body's enzymes use, rather than the forms that need converting first. In this liquid, vitamin B6 is pyridoxal 5-phosphate, riboflavin is riboflavin 5-phosphate, folate is methylfolate and vitamin B12 is methylcobalamin and adenosylcobalamin, the two forms B12 enzymes use directly. Standard complexes use pyridoxine, plain riboflavin, folic acid and cyanocobalamin, which the body converts. NIH finds absorption from the standard and active forms similar for B12 and B6, so the case for the active forms is about form, not about more getting in; folic acid also normalises homocysteine in people with the common MTHFR variant. This liquid uses the active forms throughout. Methylated B complex is the everyday name for the same thing, because methylfolate and methylcobalamin carry a methyl group; this liquid is one.

Sources: NIH Office of Dietary Supplements; peer-reviewed review (PMC5601299).

A liquid B complex, liquid B vitamins measured by the spoon, can be halved or built up. It also suits anyone who cannot swallow tablets or capsules. This one is taken as half a teaspoon in water, not as drops. Tablets need binders and a coating to hold their shape; the liquid needs a carrier and a preservative acid, which is why citric acid and potassium carbonate are in the list. The vitamins are absorbed in the small intestine whichever form they arrive in, and NIH does not find a liquid absorbed better than a swallowed tablet. For a single B vitamin rather than the set, the P5P liquid, R5P liquid and the B12 liquids are sold separately.

Sources: NIH Office of Dietary Supplements; product label.

A B complex supplies the eight B vitamins, which work together in energy-yielding metabolism and the nervous system. Thiamin, riboflavin, niacin, B6, B12, biotin and pantothenic acid each contribute to normal energy-yielding metabolism; riboflavin, niacin, B6, folate, B12 and pantothenic acid each contribute to the reduction of tiredness and fatigue; B6, folate and B12 contribute to normal red blood cell formation and to normal homocysteine metabolism; and thiamin, niacin, B6, biotin and B12 contribute to normal psychological function. These are the functions the GB register recognises for each vitamin. The B vitamins dissolve in water and are not stored in quantity, so the body needs a supply every day.

Sources: GB register of nutrition and health claims; NIH Office of Dietary Supplements.

One serving of this liquid gives 10.7 mg of vitamin B6. That is above the 10 mg a day UK guidance advises as the ceiling from supplements unless a doctor advises more, and below the European upper level of 12 mg set in 2023. Vitamin B6 is the one B vitamin where more is not better: high doses over long periods, more than 200 mg a day or lower amounts for a long time, can damage the sensory nerves. At 10.7 mg the margin to that is wide, but this is a one-serving-a-day product, not one to double. New tingling or numbness in the hands or feet means stop and speak to a GP. The other B vitamins in the serving sit well inside their UK guidance levels.

Sources: Food Standards Scotland; EFSA; NIH Office of Dietary Supplements.

Morning, with breakfast. The B vitamins are water soluble and pass through within hours, so timing is about comfort rather than absorption. Taken late in the day a B complex keeps some people awake, usually from the B6 and B12, and on an empty stomach it causes nausea in some people. Half a teaspoon in a glass of water with the first meal settles both, and the bright yellow urine from riboflavin that follows is harmless.

Sources: NIH Office of Dietary Supplements; Food Standards Scotland.

A B complex is commonly taken with magnesium, vitamin D or iron, and none of those pairings raises a known problem. It already contains folate and B12 together, so the caution NIH gives about high folic acid alongside low B12 does not apply to this product. Prescription drugs are the interactions that matter: proton pump inhibitors and other acid reducers cut absorption of B12 from food, metformin lowers B12 levels, some antiepileptic drugs lower B6 and folate, and high-dose B6 can lower blood levels of phenytoin and phenobarbital. Anyone on regular prescriptions should ask a pharmacist first.

Sources: NIH Office of Dietary Supplements.

Some people feel wired or restless on a B complex, usually from the B6 and B12. A few notice vivid dreams if it is taken late. Taking it in the morning with food, or starting on a quarter teaspoon and building up, is the usual answer. Bright yellow urine is the riboflavin leaving and is harmless. The one caution that matters is vitamin B6 over long periods at high doses, covered above. Anyone pregnant or breastfeeding, or taking prescribed tablets, should speak to a GP or pharmacist first.

Sources: NIH Office of Dietary Supplements; Food Standards Scotland.