Vitamin B12 Adenosylcobalamin Liquid

Each drop of this liquid provides 76 mcg of adenosylcobalamin, which is 3040% of the nutrient reference value. Take 1 drop per day in water with food, as the label directs, and adjust drop by drop if a practitioner has set a higher amount. One drop is one serving, and a 100ml bottle holds 1754 servings. Three sizes are available: 100ml, 250ml and 500ml.

Sources: NIH Office of Dietary Supplements; product label.

Adenosylcobalamin, also called the mitochondrial form of B12, is one of the two forms of vitamin B12 that the body's enzymes use directly. Vitamin B12 is a family of compounds built around an atom of cobalt, which is why they are called cobalamins; the forms differ only in the small group attached to that cobalt. In adenosylcobalamin that group is an adenosyl group, and it is the form used inside the mitochondria by the enzyme that handles a step in the breakdown of fats and proteins for energy.

Sources: NIH Office of Dietary Supplements.

Adenosylcobalamin drops suit anyone who wants the mitochondrial form on its own, often alongside methylcobalamin. Each active form serves a different enzyme: methylcobalamin works in the cell fluid with methionine synthase, which recycles homocysteine, and adenosylcobalamin works inside the mitochondria with the enzyme that processes certain fats and amino acids. The body converts between the two as needed, and NIH finds no evidence that absorption differs between the forms in supplements. No trial has shown one active form to outperform the other for general use. For the methylation form, see the methylcobalamin liquid. All five liquids, with the dose per drop of each, are listed together on the vitamin B12 drops page.

Sources: NIH Office of Dietary Supplements; NHS.

No: this liquid is adenosylcobalamin only, at 76 mcg per drop, in purified water with nothing else. For adenosylcobalamin, methylcobalamin and hydroxocobalamin together in one bottle, see Tri-B12, which provides 100 mcg of each form per ten-drop serving.

Sources: Product label; NIH Office of Dietary Supplements.

Adenosylcobalamin drops are for people who want the form that works inside the mitochondria, on its own or alongside methylcobalamin. That includes anyone whose methylmalonic acid result came back raised and who wants the matching form with their GP's agreement, and vegetarians and vegans, who get little of the vitamin from diet. Food Standards Scotland names older adults, people who have had stomach or bowel surgery, and vegans and vegetarians as the groups most likely to run short. Anyone who thinks they may be low in B12 should ask a GP for a blood test rather than self-treating.

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

Adenosylcobalamin drops can be held under the tongue or taken in water, and NIH finds no difference in effect between the two. Vitamin B12 in a supplement is already in free form, so it does not need the stomach acid step that releases the vitamin from food. Whichever way it is taken, a daily drop matters more than the time of day.

Sources: NIH Office of Dietary Supplements; product label.

Adenosylcobalamin is most often taken with methylcobalamin, folate, iron or the other B vitamins, and no interaction with iron is listed by NIH. Folate and vitamin B12 work together on homocysteine. NIH flags one combination to avoid: a high intake of folic acid alongside low vitamin B12 has been associated with poorer mental function in older adults. Mayo Clinic advises leaving two hours or more between a vitamin C supplement and vitamin B12. Prescription drugs are the interactions that matter. Proton pump inhibitors and other acid reducers cut absorption of the vitamin from food, and metformin lowers blood levels, so anyone on regular prescriptions should ask a pharmacist first.

Sources: NIH Office of Dietary Supplements; Mayo Clinic.

A liquid B12 lets the amount be adjusted one drop at a time, and it suits anyone who cannot swallow tablets. Tablets need binders and a coating to hold their shape; this liquid contains only adenosylcobalamin and purified water. A capsule version of the same form is also available for anyone who prefers a fixed daily amount.

Sources: NIH Office of Dietary Supplements; product label.

Adenosylcobalamin has no reported side effects at the amounts found in food or supplements. The body does not store the excess: what is not used passes out, which is why no safety ceiling has been needed. UK advice puts the level unlikely to cause harm at 2 mg a day from supplements. Observational studies have linked unusually high blood levels to poorer health outcomes, but trials giving supplements for two to seven years found little or no effect on serious illness or death rates. 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.