Micronutrient awareness and the role of B Vitamins

As seen in EatingWell

In the evolving landscape of health and wellness, micronutrients are having a moment - and with good reason. While macronutrients like fat, carbohydrates, and protein, often dominate diet and nutrition related headlines, micronutrients are small but powerful nutrients your body needs to stay energised, focused, and resilient.

Among the most essential of these are the B-complex vitamins – a family of eight water-soluble nutrients that play key roles in energy production, neurological health, DNA synthesis, red blood cell formation, and methylation. With increasingly fast-paced modern lifestyles, combined with the unique nutritional demands of our bodies and the importance of genetic individuality for determining this, it’s no wonder B-complex supplementation is drawing attention.

In this blog, we’ll unpack the following questions around B-complex use:

1. Who actually benefits?
2. When should you take B-Complex vitamins?
3. What influences how well you absorb B vitamins?

While B vitamins are widely available in a healthy, varied diet, several populations are at greater risk of deficiency or suboptimal levels and may benefit from a B-complex supplement:

• Vegans and Vegetarians: Vitamin B12 (cobalamin) is found almost exclusively in animal-derived foods. Without supplementation or fortified foods, vegans in particular are at high risk of deficiency, which can lead to anaemia and neurological issues.
• Older Adults: Absorption of B12 declines with age due to reduced stomach acid and intrinsic factor, both required for its uptake. Furthermore, aging populations may experience reduced intake of folate (B9) and pyridoxine (B6), with potential implications for cognitive health and homocysteine levels.
• Pregnant Women: Folate (B9) is essential for foetal development, and deficiencies during pregnancy can have serious consequences. B6 and B12 help support foetal brain development and maternal energy levels.
• People Under High Stress: Chronic stress increases the demand for B vitamins, particularly pantothenic acid (B5) and pyridoxine (B6), which support stress hormone regulation and neurotransmitter synthesis.
• Individuals with Malabsorption Syndromes: Conditions like celiac disease, Crohn’s disease, ulcerative colitis, and even chronic IBS can impair B-vitamin absorption. Bariatric surgery patients may also face increased risk due to structural differences in their gastrointestinal system.

Several commonly prescribed medications interfere with B-vitamin absorption or metabolism:

• Metformin: Used in type 2 diabetes, metformin impairs B12 absorption in up to 30% of long-term users. This can contribute to fatigue, peripheral neuropathy, and anaemia, hence users of Metformin should have their vitamin B12 levels measured at least annually.
• Oral Contraceptives: Long-term use can alter the demand for and deplete B6, B12, and folate levels – all nutrients that are essential for mood balance and hormonal metabolism.
• Proton Pump Inhibitors (PPIs): Vitamin B12 in food is protein-bound, requiring stomach gastric acid and an enzyme called pepsin to release vitamin B12 ready for absorption. Chronic PPI use reduces stomach acid, therefore impairing B12 release from protein-bound forms in food.
• Diuretics and Anti-epileptics: Some of these medicines can reduce levels of B1 (thiamine), B6, and folate.

Nutrigenomics studies the interaction between nutrients and genetics. Some people possess genetic variants that affect how B-vitamins are metabolised by the body, and as understanding of nutrigenomics improves, we are now able to identify those with an increased demand for B-vitamins. Below are some of the identified gene variants that are linked to increased B vitamin demand.

• MTHFR gene variants can make it harder for the body to use folic acid effectively. People with these variants may benefit from the activated form of folate, called methylfolate (5-MTHF), which supports mood, detoxification, and heart health.
• MTR and MTRR gene variants affect how the body recycles homocysteine back into methionine, using vitamin B12. Dysfunction in these enzymes, due to gene variants, can impact things like energy, mood, and heart health.
• CBS gene variants can speed up how the body clears homocysteine, which may increase the need for vitamin B6. Ensuring adequate vitamin B6 intake helps keep this system balanced.
• COMT gene variants can influence how the body breaks down dopamine and stress hormones. This process is dependent on vitamin B6 and magnesium, which can help to manage stress and ensure mental focus.

Did you know? Homocysteine is a naturally occurring by-product made when proteins are broken down. High homocysteine levels (hyperhomocysteinemia) can be a sign of low vitamin B6, B12 and folate levels. Hyperhomocysteinemia is linked to heart disease and impaired brain function, therefore maintaining a balance is important for overall health and wellness.

Summary: Whether you're a busy executive on oral contraceptives, a vegan athlete, or someone navigating genetic variants affecting methylation, a B-complex tailored to you and your individual needs may provide substantial benefit.

Take It in the Morning

Timing matters – especially with water-soluble vitamins like B-complex. B vitamins are important for energy and mental focus, as they play crucial roles in cellular energy production, neurotransmitter synthesis (e.g., serotonin, dopamine), and methylation. Taking them in the morning supports daytime alertness, cognitive performance, and metabolism.

Its best to avoid taking a B-vitamin complex at night, as certain B vitamins such as vitamin B12 (methylcobalamin), may have a mild stimulatory effect. Evening dosing could interfere with melatonin production and disrupt sleep, especially in sensitive individuals.

With or Without Food?

Taking a B-complex with a meal (preferably breakfast) can enhance absorption, especially for B1, B2, and B6, which are better absorbed when the stomach is producing digestive acids and enzymes. That said, activated forms like methylfolate and methylcobalamin may still be well absorbed without food, but combining them with a meal helps reduce the changes of any nausea or GI upset in sensitive individuals.

Pro Tip: if your B-complex suggests two daily doses, try splitting them (e.g., morning and lunch) to sustain energy in those with high stress or increased nutritional demand for B vitamins.

Enhancers of Absorption

Vitamin B12 absorption from food depends on gastric acid in the stomach. A healthy digestive environment, with sufficient stomach acid, supports absorption of several B vitamins. Intrinsic factor, a special protein made in the stomach, is essential for absorbing vitamin B12. Without intrinsic factor, which is low in pernicious anaemia, oral vitamin B12 is not absorbed effectively. In this case intravenous (IV) or intramuscular (IM) delivery of nutrients may be required to avoid deficiency. Intravenous delivery of nutrients and compounds is playing an increasingly important role in personalised health and wellness.

Taking activated forms of B-vitamins may not always enhance absorption, but is important for ensuring sufficient biological activity of B vitamins once they are absorbed or reach the bloodstream. Methylcobalamin is a more bioavailable form of vitamin B12 than cyanocobalamin, and similarly methylfolate (5-MTHF) is an activated form of folate (vitamin B9). Likewise, pyridoxal-5-phosphate is a more active form of pyridoxine (vitamin B6) that bypasses hepatic activation.

Inhibitors of Absorption

A range of factors can inhibit absorption of B-vitamins. Alcohol not only impairs absorption of vitamin B1, B6, folate (B9), and B12, but also increases their urinary excretion. Smoking can increase oxidative stress, increasing demand for and use of several B, therefore decreasing their circulating levels. Gut inflammation and imbalances in the gut microbiome can also impair B-vitamin absorption. As mentioned earlier, some medications can disrupt B vitamin uptake and metabolism. Other nutrients may compete with B-vitamins for absorption or use on the cellular level, for example high dose calcium supplements may impair vitamin B12 absorption and are therefore best taken separately.

B-complex vitamins are essential to good health – but the question isn’t simply whether to supplement, it’s how, when, and why to supplement based on your unique needs. As we enter an era of precision health – rooted in genetics, blood biomarkers, lifestyle, and individual needs – we now have the tools to allow for smarter, more targeted nutritional interventions.

Whether you're seeking more energy, optimising brain health, supporting methylation, or mitigating nutrient depletion from medications or life stressors – a high-quality, bioavailable B-complex supplement can be a powerful tool. As IV nutrient delivery continues to emerge as a modality for preventative medicine and health optimisation, combining IV therapy with genetics enables individuals to access precision B-vitamin dosing with maximal bioavailability.

By Dr Adam Jameson, Pharmacist & Precision Health Executive at REVIV