SP
StackPedia
All Comparisons

L-Threonine vs Vitamin B12 — Which Should You Take?

L-Threonine

amino acids

Typically £8–£25/month

Vitamin B12

vitamins

Typically £8–£25/month
Feature
L-Threonine
Vitamin B12
Typical Dosage
1-3 grams daily
500-1,000mcg daily
Best Form
L-Threonine powder
Methylcobalamin
Key Benefits
5 listed
5 listed
Evidence Rating
★★★★★
★★★★
Best Time
With meals, distributed throughout the day
Morning — may be energising
Upper Limit
5 grams daily
No established upper limit (water-soluble)
Side Effects
3 noted
2 noted

L-Threonine Benefits

Supports protein synthesis and muscle maintenance
Enhances immune system function
Promotes collagen and elastin production for skin health
Aids nervous system function
Supports digestive health and gut integrity

Vitamin B12 Benefits

Energy production
Nerve function and protection
Red blood cell formation
DNA synthesis
May reduce homocysteine levels

L-Threonine Side Effects

Gastrointestinal upset at high doses
Nausea or dizziness in sensitive individuals
Potential nutrient imbalances with excessive supplementation

Vitamin B12 Side Effects

Very safe — excess excreted in urine
Rare: acne at very high doses in some individuals

Can You Take L-Threonine and Vitamin B12 Together?

In most cases, L-Threonine and Vitamin B12 can be taken together safely. However, always check the interactions section of each supplement and consult a healthcare professional if you take medication or have existing health conditions.

L-Threonine: May compete with other amino acids for absorption

L-Threonine: Caution with antidepressants and neurological medications

Vitamin B12: Metformin reduces B12 absorption — supplement if on metformin

Vitamin B12: Proton pump inhibitors (PPIs) reduce absorption

Which Should You Choose?

Choose L-Threonine if your primary goal is: supports protein synthesis and muscle maintenance. Choose Vitamin B12 if your primary goal is: energy production.

Affiliate links — we may earn a small commission at no extra cost to you.

Frequently Asked Questions

Is L-Threonine better than Vitamin B12?

It depends on your goals. L-Threonine and Vitamin B12 serve different purposes and are often taken together.

Can I take L-Threonine and Vitamin B12 together?

In most cases, yes. L-Threonine and Vitamin B12 can be taken together safely. However, always check for specific interactions and consult a healthcare professional if you take medication.

What is the best time to take L-Threonine?

With meals, distributed throughout the day

What is the best time to take Vitamin B12?

Morning — may be energising

What are the side effects of L-Threonine?

Gastrointestinal upset at high doses. Nausea or dizziness in sensitive individuals. Potential nutrient imbalances with excessive supplementation.

What are the side effects of Vitamin B12?

Very safe — excess excreted in urine. Rare: acne at very high doses in some individuals.

How We Compare Supplements

This comparison is based on published clinical research, peer-reviewed studies from PubMed, and established nutritional science. We evaluate dosages based on clinically-effective amounts, not manufacturer recommendations. Benefits listed have at least moderate evidence from human studies. When evidence is limited or conflicting, we note this.

Disclaimer: This comparison is for educational purposes only and is not medical advice. Always consult a qualified healthcare professional before starting any supplement, especially if you take medication or have existing health conditions.

Related Comparisons

Popular Supplements on Amazon

As an Amazon Associate we may earn from qualifying purchases.