Why You’re Not Seeing Results from Your Supplements: Bioavailability Explained

Learn How Bioavailability Impacts the Way Your Body Absorbs Nutrients

supplements and herbs in clay bowl

If you’ve been taking supplements but not seeing the results you expect, the issue may not be with the dosage, but with bioavailability


Bioavailability refers to how well your body absorbs and utilizes the nutrients in your supplements. Even if you’re taking high-quality products, poor absorption can prevent you from reaping their full benefits. 


In this blog, we’ll explore the key factors that impact bioavailability and share practical tips to ensure you’re getting the most from your supplements.

When it comes to maximizing the effectiveness of supplements, understanding the factors that influence their bioavailability is crucial. The following key points outline several variables that impact how well your body absorbs and utilizes the nutrients in your supplements.


Factors Affecting Bioavailability

When it comes to maximizing the effectiveness of supplements, understanding the factors that influence their bioavailability is crucial. The following key points outline several variables that impact how well your body absorbs and utilizes the nutrients in your supplements.

 Key factors that influence how nutrients are absorbed:

Formulation

The chemical form of a nutrient plays a crucial role in its bioavailability. Certain vitamins and minerals are better absorbed in their natural or whole-food forms, while others require specific formulations for optimal absorption. For instance, magnesium glycinate is generally more systemically bioavailable than magnesium oxide. (1)

Or, vitamin B6 in the common supplement form, pyridoxine hydrochloride (PNH), must be converted in the liver to its active form, pyridoxal-5-phosphate (P5P), to function effectively. Individuals with genetic polymorphisms or impaired liver function may struggle with this conversion, leading to insufficient B6 activity despite supplementation. This can result in mood disturbances, nerve pain, and even toxicity from the accumulation of excess inactive B6.

Opting for B6 supplements in the active P5P form ensures better absorption and immediate usability, minimizing the risk of complications while supporting neurotransmitter synthesis, homocysteine metabolism, and overall nervous system health. (2) 

In addition to B6 and magnesium, here are a few other examples where the form of a nutrient impacts its bioavailability:

Iron: Iron comes in two forms—heme and non-heme. Heme iron, found in animal sources like red meat, is much more bioavailable and easily absorbed than non-heme iron from plant sources. Non-heme iron often requires enhancers like vitamin C to improve absorption, which can be important for vegetarians or vegans. (3) 

Calcium: Calcium citrate is more bioavailable than calcium carbonate, especially for individuals with low stomach acid. Calcium carbonate needs stomach acid to dissolve, while calcium citrate is more easily absorbed, making it a better option for those with digestive issues. (4)  

Curcumin: The active ingredient in turmeric, curcumin, is poorly absorbed in its natural form. Combining it with black pepper (piperine) or using liposomal delivery systems can significantly enhance its bioavailability, ensuring the body can utilize it more effectively. (5) 

Folate: Many people have difficulty converting folic acid (the synthetic form of folate) into its active form due to genetic variations like MTHFR mutations. Methylfolate, the active form, bypasses this conversion, making it more bioavailable for those with these mutations. (6)  


Delivery Method

The way a supplement is delivered can also affect bioavailability. 

For instance, CBD, glutathione, and curcumin, are notoriously difficult for the body to absorb. 

Additionally, vitamins like Vitamins A, E, D, and K can have similar bioavailability issues due to their fat-soluble nature. (7) 

Vitamin C, on the other hand, is a water-soluble nutrient, which means it dissolves in water and is not stored by the body. As a result, maintaining elevated levels of vitamin C through standard supplementation can be challenging. Typically, 70-90% of vitamin C is absorbed at daily intakes of 30-180 mg, but when larger doses—over 1 gram—are consumed, absorption drops to under 50%, with the excess being excreted in urine. (8) This means that traditional vitamin C supplements, whether in powder or capsule form, may be inefficient, leading to nothing more than expensive urine. 

Various nutrients, such as CBD, fat soluble vitamins like D, A, E, and K, and vitamin C, can be “packaged” into liposomes and subsequently delivered to our cells, significantly improving nutrient absorption. Liposomal delivery systems encapsulate nutrients in lipid nanoparticles, which can enhance absorption by protecting the nutrients from degradation in the digestive system and facilitating their direct uptake by cells. (9)  

When it comes to probiotics, spore-based probiotics are the better choice for their superior stability and effectiveness compared to traditional store-bought probiotics. Unlike conventional probiotics, which are often fragile and may not survive the acidic environment of the stomach, spore-based probiotics have a protective outer shell that allows them to withstand harsh conditions. 

This unique structure enables them to reach the intestines intact, where they can colonize and exert their beneficial effects. Additionally, spore-based probiotics are more resilient to temperature and environmental factors, ensuring a longer shelf life without requiring refrigeration. Their enhanced survivability and ability to create lasting colonies in the gut make them a more reliable option for supporting digestive health. (10) 


Digestive Health

Digestive health is a critical factor in the bioavailability of supplements. Conditions such as low stomach acid, acid reflux, gut dysbiosis, leaky gut, or malabsorption issues can significantly impair the body's ability to absorb nutrients effectively. 

Addressing these underlying issues can enhance nutrient uptake and overall health. For example, high-quality probiotics, stomach acid support, bitters, or digestive enzymes may be necessary for optimizing to increase the absorption of vitamins, minerals, and other key nutrients. Prioritizing gut health ensures you're maximizing the benefits of your supplements. (11) 


Timing and Interactions

Timing and interactions with food or other supplements play a significant role in how well your body absorbs certain nutrients. 

Some vitamins and minerals, like fat-soluble vitamins (A, D, E, K), require fat for better absorption.

Others, such as calcium and magnesium or zinc and copper can compete with each other when taken together, while others depend on other factors such as minerals and B12 require robust stomach acid and Vitamin D requires magnesium and K2 for optimizing their effectiveness.

Additionally, taking certain supplements in the morning versus at night can affect their efficacy, as digestion and metabolism fluctuate throughout the day. 

For example, taking magnesium at bedtime has a calming effect and can improve sleep. B vitamins, on the other hand, should be taken in the morning.

Ensuring the right timing and understanding positive and negative interactions can optimize bioavailability and the benefits of supplementation. (12) 


Watch Out for Additives

Additives like fillers, binders, and coatings found in some supplements can hinder the absorption of active ingredients, limiting their effectiveness, causing harm,  and reducing bioavailability. 

Common additives may even cause digestive discomfort in sensitive individuals, further impacting nutrient absorption. (13) 

Opting for clean, additive-free supplements ensures you're getting the full benefit of the nutrients without unnecessary and potentially harmful ingredients. This attention to quality not only promotes better bioavailability but also supports overall gut health.


Why "One-Size-Fits-All" Supplements Don't Work: The Importance of Proper Dosing

Many supplements, particularly multivitamins or green powders, often provide minimal doses of a wide range of nutrients, which may not be enough to yield meaningful health benefits. Instead of relying on a "one-size-fits-all" solution, work with a functional medicine doctor find out what you’re defiecint in and why.

It's more effective to understand your unique nutrient needs by undergoing a comprehensive health assessment with lab testing. 

This targeted approach allows you to supplement specifically what your body lacks, ensuring you get the right dose to support your health optimally. By  personalizing your supplement regime, you're more likely to see real results and avoid unnecessary nutrients that you're not lacking.


Tailor Supplementation to Individual Needs

Nutrient needs can vary dramatically from person to person, highlighting the importance of personalized supplementation

For example, while one person may thrive on 600mg of magnesium citrate, someone else might experience digestive distress, such as diarrhea, and may benefit more from a gentler form like magnesium glycinate. 

Additionally, even two individuals with the same MTHFR gene mutation can have different needs; one might require higher levels of B-vitamins, while the other could struggle with absorption issues and need more digestive support or certain amino acids. 

Another person may have high oxidative stress, where antioxidant support may be necessary, but the root issue may be ineffective detoxification pathways and that is what needs to be addressed to improve their health long-term. 

Personalized assessments ensure your supplementation is tailored to your body’s specific needs and root causes are addressed for optimal results.



Optimize Your Supplement Routine with a Personalized Approach

When it comes to optimizing your supplement routine, a personalized approach is key. A one-size-fits-all strategy often overlooks individual variations in nutrient needs, absorption rates, and overall health status. 

At Denver Sports and Holistic Medicine, Dr. Martina Sturm, will partner with you to help identify your body’s specific deficiencies, toxicities, and metabolic patterns. We will do a comprehensive assessment and functional lab work to ensure we’re addressing the root causes of your health concerns and receiving the precise nutrients your body needs for optimal health.

Functional lab testing can identify micronutrient imbalances, detoxification issues, or hormonal fluctuations that standard blood work might miss. Armed with these insights, we can take a targeted approach to supplementation—customizing doses, selecting bioavailable forms of nutrients, and addressing underlying health issues like gut health or inflammation. 

This tailored method not only maximizes the efficacy of your supplements but also supports long-term wellness and prevents unnecessary nutrient overload.

Ready to Elevate Your Health?

Request a free 15-minute consultation with Dr. Martina Sturm at Denver Sports and Holistic Medicine today to learn how a personalized approach to your health and supplement regime so that you can change your health outcomes.

Our goal is to help treat your health concerns and optimize your health and longevity so you can live your best life!



Resources

  1. The 4 Most Bioavailable Forms Of Magnesium | mindbodygreen

  2. Pyridoxal 5 Phosphate (P5P): Highly Bioavailable Vitamin B6 | by Isotrope | Medium

  3. Dietary Iron - StatPearls - NCBI Bookshelf 

  4. Meta-analysis of calcium bioavailability: a comparison of calcium citrate with calcium carbonate - PubMed 

  5. Improving Curcumin Bioavailability: Current Strategies and Future Perspectives

  6. Active Folate Versus Folic Acid: The Role of 5-MTHF (Methylfolate) in Human Health - PMC 

  7. Fat-Soluble Vitamins - Diet and Health - NCBI Bookshelf 

  8. Vitamin C - Health Professional Fact Sheet  

  9. Current Applications of Liposomes for the Delivery of Vitamins: A Systematic Review  

  10. Bacillus Probiotics: Spore Germination in the Gastrointestinal Tract - PMC 

  11. Small and Large Intestine (I): Malabsorption of Nutrients - PMC 

  12. Supplements Timing for Optimal Absorption

  13. Inactive Ingredients / Excipients in Supplements - ConsumerLab.com