Low B12 can cause issues with anaemia, fatigue, and lack of focus. This is because Vitamin B12 is essential for making red blood cells, which carry oxygen to your muscles and organs – including your brain.
Many people suffering from fatigue, lack of energy and headaches choose to take a B12 supplement in the form of a daily pill, but is this as effective at treating symptoms as a B12 injection?
In this blog, we’ll look at the differences between B12 injections and B12 tablets, and which option is best for reducing fatigue and improving focus.
B12 oral supplements – How many are equivalent to one B12 injection?
Usually, B12 capsules or tablets contain doses of between 50 and 5,000mcg, whilst B12 injections usually contain 1,000mcg.
This leads many people to ask the question, “How many B12 tablets do I need to take to equal one B12 injection?”
It’s not actually that simple. As your body absorbs B12 oral supplements and B12 injections in different ways, a dose of 1,000mcg of B12 taken orally is not equivalent to a B12 injection of 1,000mcg.
According to research conducted in 2008, the body only absorbs about 1.3% of a 1,000 mcg oral dose of B12. On the other hand, absorption rates from B12 injections of the same amount were found to be between 55% and 97%.
B12 injections are absorbed much better by the body because they are administered intramuscularly (into the muscle), and therefore directly into the blood. B12 tablets must pass through the digestive system, which leads to much poorer absorption rates.
B12 dosage and frequency
Because B12 tablets aren’t absorbed into the body as well as injections, they must be taken daily. The dose is often very high, as most of it will pass through your digestive system and be excreted by your body. This means that the effects will happen more gradually, with symptoms often taking some time to improve.
The superior rate of absorption of B12 injections means that they can be administered every 3-6 months. Your B12 levels will immediately increase, leading to almost instant improvements in your symptoms. In fact, most people notice they have better focus and decreased fatigue within the first 24-48 hours.
B12 injections for pernicious anaemia
Harvard Health Publishing explains that intramuscular B12 injections are particularly helpful for treating pernicious anaemia. This is an autoimmune condition that affects the stomach, preventing the body from absorbing B12. Untreated pernicious anaemia can cause serious medical issues, which include irreversible damage to the nervous system.
Because fast-acting B12 injections bypass the stomach, they are the most effective way to treat this condition.