Are My Supplements Even Working?
By Marla Feingold MS, CNS, CKNS, LD
Why Am I Still Low on Vitamins?
It’s frustrating! You’re diligent with your supplements, yet your blood tests still show deficiencies like low vitamin D or B12. If you’re taking your multivitamins, omega-3s, and magnesium regularly but still not seeing results, it could be due to some common factors.
Why Do Supplements Not Always Work as Expected?
Even with top-quality supplements, there are a few reasons why you might not be absorbing nutrients as efficiently as you’d like:
- Gut Health: A poorly functioning digestive system can hinder your body's ability to absorb essential nutrients, particularly fat-soluble vitamins like A, D, E, and K. It can also affect your gut microbiome and how effectively your gut bacteria synthesize key nutrients.
- Nutrient Interactions: Vitamins and minerals can interfere with each other’s absorption. For example, calcium can block iron absorption if taken together.
- Timing and Pairing: Certain vitamins work better when paired with others. For instance, vitamin C enhances iron absorption, so taking them together is more effective than taking iron alone.
- Form of the Supplement: Not all supplements are equally bioavailable. For example, methylcobalamin (a form of vitamin B12) is more readily absorbed and utilized by the body than cyanocobalamin.
How Does My Body Absorb Nutrients?
Your body has a well-organized system for absorbing nutrients, and it starts the moment food enters your mouth:
- Digestion breaks food down into basic components, amino acids, fatty acids, glucose, vitamins, and minerals.
- The small intestine is where most nutrient absorption happens, allowing nutrients to pass into the bloodstream.
- Fat-soluble vitamins (A, D, E, K) need fat, such as that from avocado or olive oil, for proper absorption.
- Water-soluble vitamins (B vitamins, vitamin C) dissolve in water and are therefore absorbed quickly, but since they aren’t stored well in the body, you need a steady supply.
Can Genetics Affect How I Process Vitamins?
Yes, your genetic makeup can influence how your body manages certain vitamins. Some key points:
- Variants of the MTHFR gene can make it harder for your body to convert folic acid into its active form (methylfolate), which is important for DNA repair and energy production.
- Genetic variants in the Vitamin D receptor (VDR) may affect how your body responds to vitamin D, even if you're getting enough from sun exposure or supplements.
- For instance, CYP2R1 gene variants can impact how efficiently you convert vitamin D into its active form (calcitriol), leading to suboptimal vitamin D levels.
- Certain transport proteins such as TCN gene help shuttle B12 through your body, —if these are inefficient, nutrient absorption can be impaired.
What Can You Do?
- Choose bio-available supplements: Look for forms of vitamins that your body can easily use, like methylated B vitamins or chelated minerals.
- Mind your pairings: For better absorption, pair magnesium with evening meals, take iron with vitamin C, and consume fat-soluble vitamins with healthy fats.
- Track progress: Regular blood tests can help you see if your supplements are working as intended.
- Consider genetic testing: A nutrigenomics test can reveal personalized insights into your body’s unique nutritional needs.
Conclusion
Supplements aren’t a quick fix, but when used strategically, they can complement a healthy lifestyle. Understanding how your body absorbs nutrients and, the factors that affect this process can help you make smarter choices for your health.