Boost Your Energy: How Functional Medicine Treats Vitamin B12 Deficiency
Posted on May 5, 2025
Always tired even after sleeping well? Feeling foggy-headed or have tingling hands and feet? Maybe you’re moody for no reason? You could be one of the millions with vitamin B12 deficiency.
More Common Than You Think
Many people don’t know they have low B12. About 6% of folks under 60 have it, and this jumps to 20% in people over 60. Many more people have levels that are not optimal. Too many people don’t know about the risks and symptoms of low B12.
Why Your Body Needs B12
B12 is a vitamin that contains a mineral called cobalt. Your body uses it in two main forms: methylcobalamin and 5-deoxyadenosylcobalamin.
Your body needs B12 for:
- Healthy nerves: B12 helps build the coating around your nerves so messages travel correctly.
- Making new cells: B12 helps your body create and fix DNA. Without enough B12, your cells can’t divide properly.
- Healthy blood: B12 helps make normal red blood cells. Without it, you get fewer, bigger blood cells that don’t work well.
- Energy: B12 helps turn food into energy you can use.
Signs Your B12 Might Be Low
Look for these common signs:
Body symptoms:
- Always tired
- Cold hands and feet
- Pale skin
- Trouble breathing
- Heart racing
- Feeling dizzy
- Headaches
Brain and mood symptoms:
- Numb or tingling hands and feet
- Trouble walking
- Feeling confused
- Feeling sad or worried
- Memory problems
Digestive symptoms:
- Sore, swollen tongue
- Not feeling hungry
- Changes in bathroom habits
Who’s More Likely to Have Low B12?
These groups often have B12 problems:
- Vegans and vegetarians: Plants don’t naturally have B12.
- People over 65: Older adults often need B12 testing.
- People with digestive problems: Conditions like celiac disease and Crohn’s disease make it hard to absorb B12.
- After stomach surgery: Operations like gastric bypass make it harder to get B12 from food.
- People with certain immune problems: Some conditions attack the cells needed to absorb B12.
- People taking certain medicines: Some drugs lower B12 levels, like acid reducers, birth control pills, and diabetes medicine (metformin).
How Functional Medicine Treats Low B12
Functional medicine doesn’t just give you a standard pill. It looks at your whole body and finds the real reason for your B12 problem. Here’s how it works:
1. Better Testing
First, you’ll get blood tests to check for anemia and B12 levels. Low B12 is below 150 pg/mL.
For better results, especially if your levels are borderline, you might also get tested for:
- Homocysteine (high if above 15)
- Methylmalonic acid (high if above 0.271)
2. Custom B12 Supplements
Based on how severe your problem is and what’s causing it, your doctor might suggest:
For severe cases or nerve problems: B12 shots are often best for quick results. These are usually given weekly at first, then monthly.
British medical guidelines say people who can’t absorb B12 well should get 1000 µg shots once every two months after the first few doses.
For people with bowel diseases, American gut doctors suggest 1000 µg B12 shots every 1-4 weeks for life.
For mild to moderate cases: High-dose B12 pills (500 to 1000 μg daily) can work even for people with some absorption issues. Your body can absorb some B12 even without the special protein that usually helps.
Studies show that high-dose B12 pills can fix blood levels and improve symptoms even in people with serious absorption problems. Pills are easier to take and cost less than shots.
Other ways to take B12: Nasal spray (like Nascobal) is another option, mainly for keeping B12 levels up after they’re fixed. The usual dose is one 500 μg spray in one nostril weekly.
3. Eating More B12-Rich Foods
- If you eat meat: Liver, shellfish, fish, eggs, and dairy products
- If you’re vegetarian: Dairy products, eggs, and B12-fortified foods
- If you’re vegan: Nutritional yeast, fortified plant milks, cereals, and supplements
4. Fixing the Root Causes
Beyond just giving B12, functional medicine works to fix the underlying problems:
- Healing gut inflammation that stops B12 absorption
- Changing medicines that may be lowering your B12
- Helping your stomach make more acid if it’s too low
- Treating immune problems that might be causing absorption issues
How You’ll Feel Better
With the right treatment, most people notice big improvements:
- More energy within days or weeks
- Better mood and clearer thinking
- Less tingling and numbness
- Better exercise and recovery
- Stronger immune system
- Better sleep
How fast you get better depends on how severe and long-lasting your deficiency was. Nerve problems may take longer to heal, and some long-term effects might be permanent.
Preventing B12 Problems
To prevent B12 deficiency, make sure you get enough B12 through food or supplements. Regular testing is important for people at risk to catch problems early.
If you’re always tired or have any symptoms mentioned above, don’t just write it off as “getting older” or “being busy.” Talk to a doctor who knows about functional medicine approaches to B12 deficiency. With proper diagnosis and treatment, you could soon feel energetic and healthy again.
This article is for information only and is not medical advice. Always talk to a healthcare professional before starting any supplements.
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