B12 injections are highly effective and worth it if you have a diagnosed deficiency, rapidly replenishing levels and boosting energy, focus, mood, and nerve health, but for people with normal levels, oral supplements are usually as good, and injections don't offer magical benefits like weight loss or extreme energy, though they're generally safe with low overdose risk.
Are vitamin B-12 injections helpful for weight loss? There's no solid proof that vitamin B-12 shots, also called injections, help you lose weight. Vitamin B-12 is a water-soluble B complex vitamin. It's found naturally in many foods, such as meat, fish and dairy products.
Your doctor likely stopped B12 injections due to following standard guidelines suggesting oral supplements or for reasons like cost/logistics (especially during the pandemic), but this can be risky; the main reasons are often a perceived 'normal' blood test (which doesn't always reflect cell levels) or a guideline shift, but you may still need injections for neurological symptoms or poor absorption, so discuss your symptoms urgently with your doctor and ask for clear evidence for the change.
People who are deficient in vitamin B12 are often prescribed B12 shots. This method is a very effective way of reversing or preventing a deficiency because it allows for 100% absorption directly into the tissues.
Common side effects
To make sure it's safe for you, tell your doctor before having hydroxocobalamin if you:
Symptoms such as pins and needles, disturbed vision, a sore and red tongue, mouth ulcers, muscle weakness and problems with balancing and walking, psychological problems such as depression and confusion, problems with memory, understanding and judgement could also be related to B12 deficiency.
If you're dealing with a severe deficiency, low energy, or digestive issues, Vitamin B12 Injections are likely the better choice due to their high absorption rate and fast-acting benefits. Oral supplements may be sufficient if you're maintaining good health and prefer a daily routine.
Vitamin B12 or folate deficiency anaemia can cause a wide range of symptoms. These usually develop gradually, but can worsen if the condition goes untreated.
Vitamin B12 shots help replenish essential nutrients that support energy metabolism, nerve signaling, and healthy red blood cell production, which may ease ongoing fatigue. By supporting cellular function and brain health, B12 shot can promote clearer thinking, improved stamina, and a renewed sense of balance.
Oral vitamin B12 replacement at 1000 μg daily is an adequate alternative to IM B12 injections.
However, it may take a few days or weeks before your vitamin B12 levels and symptoms (such as extreme tiredness or lack of energy) start to improve. Are there any long-term side effects? It's OK to have hydroxocobalamin injections for a long time. Some people will need to have them for the rest of their lives.
While celebrating your B12 shot or unwinding after a long week might involve a drink, it's best to avoid alcohol for at least 48 hours after your injection.
In fact, some studies have even suggested the opposite. For instance, one study noted that individuals who regularly took vitamin B12 supplements gained between 2.5 to 17 fewer pounds (1.2 to 7.7 kg) over a decade than those who didn't supplement.
Causes of Vitamin B12 deficiency
Typically, you'll enjoy the benefits for about one to two weeks. But the exact duration depends on your body's needs, how deficient you are, and your overall lifestyle. Your current B12 levels, metabolism, diet, and how often you receive injections all play a role.
B12 deficiency can trigger specific food cravings, most notably for meat, fish, or eggs, as the body seeks animal-based sources to replenish the vitamin, especially in those on vegetarian/vegan diets or older adults. While cravings for sugary or salty foods can also signal general B-vitamin issues, the distinct urge for protein-rich animal products is a key indicator, but professional testing is crucial for confirmation.
There's no conclusive evidence that vitamin B12 shots help with weight loss. People with a BMI over 30 sometimes have low vitamin B12 levels. Treatment with B12 shots can improve low B12 levels and boost energy.
The foods highest in Vitamin B12 are animal products, with clams and liver (beef, lamb) being exceptionally rich sources, often providing several hundred percent of the daily value in a single serving, alongside seafood like mussels, sardines, and salmon, dairy, eggs, and fortified cereals and nutritional yeast for vegans.
What side effects may I notice from receiving this medication? Side effects that you should report to your care team as soon as possible: Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat. Swelling of the ankles, hands, or feet.
The Upper Buttocks (Gluteus Medius Muscle)
The upper buttocks area, specifically the gluteus medius muscle, is frequently used by healthcare professionals for B12 injections. This site is located in the upper, outer part of the buttock—not the area you sit on.
Symptoms of vitamin B12 or folate deficiency
Cutaneous manifestations associated with vitamin B12 deficiency are skin hyperpigmentation, vitiligo, angular stomatitis, and hair changes. A diagnosis of vitamin B12 deficiency is often overlooked in its early stages because these signs are not specific to vitamin B12 deficiency alone.
Lack of vitamin B12 in your diet: People who don't eat enough foods that have vitamin B12 or don't eat foods fortified with B12 can develop a deficiency. Gastritis: Gastritis is inflammation of the stomach lining, and it's a common cause of vitamin B12 deficiency.
The Boots Vitamin B12 Blood Test Kit checks your vitamin B12 levels, using a finger-prick blood sample. Use of this kit requires internet access. All personal data in relation to this product, services and online platforms are collected and processed by MyHealthChecked.