Benefits of B12 Injections

Vitamin B12 supplement is very popular. Learn how you can benefit from it.

learn what health problems could be caused by a low b12 level

Vitamin B12 is a vitamin that plays an essential role in the body. It helps in red blood cell production and helps break down fats, proteins, and carbohydrates. It also provides energy for your muscles, nerves, and brain health. Low vitamin B12 can lead to anaemia (lack of red blood cells), weakness, fatigue, and even dementia. B12 injections are one of the most common ways to get this vitamin into your body. If you have low levels, you may need to take it by mouth or get regular B12 shots for a long time. Some people need B12 injections to treat a deficiency. Others might choose to take them if they have trouble absorbing food-based vitamins.

Vitamin B12 injections are a vital part of any vitamin regimen. But there's more to the story than what you read on a bottle of supplements. This article explores how B12 works, who needs it, and how to get enough in your diet.

How do B12 injections work?

B12 injections can give you more energy, help you lose weight, improve your memory and mood, and get a good night's sleep. But do they work? That depends on what you're looking for.

B12 injections can be used to treat several conditions and can help boost your health in many ways. For example, they can ease symptoms of fatigue, which is common in people who don't get enough B12 from their diets or supplements. Your doctor might also recommend B12 shots if you're anaemic or have pernicious anaemia (an autoimmune disorder). They can also help boost your immune system and decrease inflammation. And some research has indicated that B12 injections might effectively treat neurological conditions such as Parkinson's disease, multiple sclerosis, and Alzheimer's disease. However, B12 injections won't cure everything. For example, they won't help you lose weight or boost your energy levels if you're not getting other vitamins in your diet.

As an adult over age 50 or so who eats a balanced diet that includes animal products (including dairy) every day but still feels tired all the time, B12 shots might be worth a try. Injections are unnecessary if you take other forms of B12 (like pills or sublinguals). The problem is that these other methods tend to be less effective than injections—and may not be as effective at kicking up energy levels if you're an older adult trying to boost them after years of being low in this essential vitamin.

Who should consider B12 injections?

The normal range of vitamin B12 can vary depending on the test used. In general, it is between 200-900 pg/mL. A deficiency is defined as a level below 200 pg/mL. The symptoms of B12 deficiency can vary from person to person. Some people may experience no visible symptoms at all, while others may have various symptoms. You may need to get B12 injections if you experience the following common symptoms:

  • fatigue and weakness

  • numbness or tingling in the hands or feet

  • difficulty maintaining balance when walking

  • headaches and migraines

  • joint pain and stiffness

  • dizziness, confusion, memory loss, and brain fog

  • nausea and vomiting

  • depression

  • constipation

  • diarrhoea

  • decreased appetite and weight loss without trying to lose weight (in which case it could be cancer)

  • insomnia (difficulty sleeping)

You may also have a sore tongue, mouth ulcers and red blood cell changes. If you're pregnant, low levels of B12 can affect your baby's brain development.

Take this folate blood test to determine the amount of vitamin B12 in your blood.


What benefits can I get from B12 injections?

Vitamin B12 is vital for making red blood cells and keeping the nervous system healthy. It plays a crucial role in other body processes, such as making DNA, which is a building block for all cells in the body. If you don't have enough B12, your body can't make enough new cells to replace old ones, including red blood cells that carry oxygen. Without these new cells, you'll feel tired and weak. There are several reasons why a person should consider B12 injections. The following are the immediate health benefits you can get from B12 shots.

  • If you have dietary restrictions, e.g., vegetarian or vegan, it's hard to get enough B12 in your diet. B12 injections are an excellent option for vegetarians and vegans who want an easy way to get their daily requirement of this essential vitamin.

  • B12 injections can help your body make more red blood cells if you have anaemia or are pregnant.

  • If you have a vitamin B12 deficiency, taking oral supplements may not be enough to help your body recover from this condition. Injections can give you an immediate boost of the vitamin without having to wait for it to metabolize in your digestive tract. In addition, oral B12 supplements are only partially absorbed by your body and may not be effective. Taking an oral B12 supplement can also cause a temporary increase in homocysteine levels, which can increase your risk for heart disease.

  • The absorption of B12 from food is very inefficient, and most people need more than they can get from their food alone, especially older adults. Other conditions can also cause malabsorption of B12 from food, such as Crohn's disease, Celiac disease and some types of liver disease. Some medications can interfere with B12 absorption, including antibiotics like tetracycline and metformin for diabetes. Thus, B12 shots are a better option than an oral supplement.

  • B12 injections are very easy to take and have no side effects.

  • B12 injections are suitable for your eye health. A study found that people with higher vitamin B12 were less likely to develop age-related macular degeneration, which can progress to blindness.

  • B12 improves metabolism and helps you lose weight. This is because it helps turn the food you consume into energy instead of storing it as fat.

  • In some cases, B12 injections can be used to treat other health issues. For example, if you have pernicious anaemia, a type of anaemia caused by low levels of vitamin B12. In this case, the injection is used as a long-term treatment option.

Are B12 injections safe?

B12 injections are generally safe. They're given in small doses and are usually well-tolerated by most people. The main risk is an allergic reaction to the preservative used in some vitamin injections (propylene glycol). If you're allergic to this ingredient, talk to your doctor first before going ahead with a B12 shot.

Here's an effective folate blood test to measure if you have a B12 deficiency.

Other side effects of B12 injections are the same as those of other forms of the vitamin:

  • Nausea or stomach upset is possible if you take too much in one day (but not likely).

  • Some people also have a mild skin reaction (swelling, redness, or soreness) at the injection site after getting B12 shots—this usually goes away within a few days.

While B12 injections are safe, you should always consult your doctor before getting one if you're planning on getting B12 injections. It's important to know if you have any existing conditions that could be affected by a B12 shot—such as anaemia or heart disease. You can get b12 injections at a local pharmacy or online.

How often should you get a B12 shot?

It would help if you got a B12 shot at least once a week, but most people need more regular injections. The exact amount of B12 you need depends on your body's needs and how much you have stored in your liver. Check with your doctor for a blood test to determine if you require more B12 than what's in food.

In general, whether you get a B12 shot once every week or once every month, the more often you do it, the more effective it will be. The less frequently you get them, the less effective they are.

How much is a B12 injection?

The cost of B12 injections varies depending on which country you live in and where you go to get them. In the UK, a single B12 injection will generally cost between £1-2.50 (US$1.55 to US$3.08). When searching for a place to buy them online in the US, prices range from $20 to over $100. It depends on where you purchase them from and your provider's brand or formulation. In Australia, prices range from about AU$47 to AU$100 per injection, which is about five times more than what it costs in the UK!

What can you not take with a B12 injection?

B12 should not be taken alongside antacids, as the acidity in these products can prevent the absorption of this vitamin. B12 is a water-soluble vitamin which can be easily flushed from your body if you take too much of it. As such, taking other water-soluble vitamins with B12 isn't recommended as they may decrease its effectiveness. This includes folic acid and vitamin C. Vitamin B12 can also interact with the following medications:

  • Cholestyramine (Questran) and colestipol (Colestid). These are used to lower cholesterol.

  • Didanosine (Videx EC) and Epivir. They are used to treat HIV infection.

  • Phenobarbital and primidone are used to control seizures and treat sleep disorders.

  • Sucralfate (Carafate) is used to treat ulcers.

  • Metformin (Glucophage) and glyburide (Diaformin). These are used to control blood sugar in people with diabetes and can put you at greater risk for lactic acidosis if taken with B12.

  • Oral contraceptives and injections of hormones (birth control), such as Depo-Provera. These contain estrogen, which may decrease the effectiveness of B12.

  • Chloroquine (Aralen) is a medication for malaria.

  • Sulfamethoxazole with trimethoprim (Bactrim, Septra) is used to treat infections caused by certain bacteria.

  • Esomeprazole (Nexium), pantoprazole (Protonix) and lansoprazole (Prevacid). These are used to treat gastroesophageal reflux disease.

  • Famotidine (Pepcid AC) is used to suppress acid in the stomach and treat heartburn.

  • Antibiotics in general. Taking B12 and antibiotics at the same time can cause your body to absorb both, which is not a good thing. Antibiotics can destroy the beneficial bacteria in your gut, so it's essential to take them separately from any probiotic supplements or foods you might be taking to restore that balance. You should also avoid taking them together with iron supplements, calcium supplements, and antacids—anything that could affect your gut microbiome in some way.

Inform your doctor if you have any of the medications listed above before receiving B12 shots to avoid undesirable effects.

Dietary sources of B12

If you are on a vegetarian or vegan diet, then the best way to achieve your daily dose of B12 is from foods like:

  • dark leafy greens

  • fortified foods like cereals

  • plant-based milk

There are also some plant-based sources of B12, such as seaweed and spirulina, but they're not always reliable. If you're vegetarian or vegan, it's best to consult a doctor about how to get enough B12 into your diet without taking supplements. This vitamin is naturally found in animal foods like eggs, meat, and dairy. They can help meat eaters meet their nutritional needs.

The takeaway

Vitamin B12 is among the essential vitamins you can take to stay healthy. It has a wide range of benefits, from preventing memory loss and improving brain function to keeping your heart healthy and treating certain medical conditions. It can also play a role in preventing cancer and even treating it, which is why it's essential to take a B12 supplement. And while you can get B12 from meat and fish, vegans should be especially careful about getting enough of this vital nutrient.

B12 injections are safe and effective, but they do come with some risks. They can be pricey and cause side effects such as dizziness, nausea or even headache. If you feel something is absent from your diet or missing out on some essential nutrients, talk with your doctor about supplementing with vitamin B12. It's also a good idea to speak with your doctor before considering any new medications or supplements. This will help ensure that the combination of drugs and vitamins won't have health consequences and adverse effects on your body or mind. To determine the amount of B12 in your blood, you can take this folate blood test.


Learn more about vitamin B12 on Welzo by browsing our topics what is vitamin b12 and why do I feel worse after a vitamin B12 injection. 

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