Update 8/1/20. Can vitamin B12 help people lose weight? I'm asked this question more than one might think and oddly, most of these questions come from the state of Maryland. That makes me think that someone in Maryland is using B12 for weight loss. But does it really work or is it a scam? Let’s now discuss vitamin B 12, and whether it can help people lose weight and see what we can discover.
What is Vitamin B12
Vitamin B12 is a member of the B complex family of vitamins. Other B vitamins include niacin and folate/folic acid.
Like other members of this family, B12 is also a “water-soluble” vitamin. Many people take this to mean that we excrete (in other words, urinate ) excess B12 from the body.
Vitamin B 12 is one of the nutrients we need to make red blood cells, which carry oxygen through the body. You use the oxygen to help make energy. If your red blood cells are not working properly, anemia can result. One of the signs of anemia is being tired. Because of this fact, people often say that vitamin B12 will give you extra energy or “pep” to get through a hard or stressful day.
The “vitamin B12 gives you energy” connection is also probably why energy drinks like 5 Hour Energy contain B12 as well.
There was a very small study of B12 helping fatigue but it was done in the early 1970s, had problems with how the study was conducted and to my knowledge, was never replicated.
Do We Pee B12 Out Of The Body?
Even though it’s a water-soluble vitamin, it takes about 2-5 years before we run out of vitamin B12.
We store vitamin B12 in the body. Those who may run out of B12 faster include
- older adults
- alcoholics
- vegans
- people who take certain medicines (like metformin)
- people who have undergone weight loss surgery (bariatric surgery)
Why do older folks run out of B12? It's because they sometimes lose their ability to absorb it. After several years, they run out of B 12 and this is why a doctor will sometimes give them a B12 shot.
Vitamin B12 and Weight Loss
Do vitamin B12 injections burn fat and help people lose weight? What about supplements? There is no good clinical proof for this. But, if that's correct, why do some doctors and weight loss clinics give people this vitamin?
This is what I think is going on:
It’s possible that getting weekly injections of vitamin B12 may help people adhere to their weight loss goals. In other words, if they know they have to return to the clinic each week and get weighed and get a B12 shot, then they may be more likely to stick to the diet. Weekly meetings like this might actually be one of the reasons that Weight Watchers is so successful at helping people lose weight.
It’s also important to note that people usually don’t just get shots of B12; they also get a low-calorie diet to follow also.
What about the Placebo effect. In other words, if you think it works, it likely will work. Being told by somebody (like a doctor or a professional wearing a white coat) that B12 helps weight loss might be a strong enough stimulus to make people believe in the efficacy of this nutrient.
Many overweight people also have type II diabetes. As such, they may be taking a drug called Glucophage (metformin). Several studies have noted that this drug can lower B12 levels. Therefore, it’s possible that a doctor may give vitamin B12 injections to counteract this effect.
Does Vitamin B12 Help Weight Loss
There may be medical reasons why a doctor would prescribe vitamin B12. But, for weight loss, there is no good proof.
What do you think?