Supplement Toxicity: Why Food-Based Nutrients Are Better

by Kate Morton

At Funk It Wellness, we believe in the power of real food for optimal health. While synthetic vitamins are common in supplements, they don’t always work the same way in your body as nutrients from whole foods. One major reason for this is bioavailability—the extent to which a nutrient is absorbed and utilized by the body. Understanding the difference between synthetic and food-based vitamins can help you make the best choices for your health. That’s why we prioritize whole-food ingredients in our products, like CycleBites and our seed cycling blends, which provide essential nutrients in their most natural and absorbable forms.

At Funk It Wellness, we believe that real food should be the foundation of good nutrition. While supplements can be helpful in certain situations, they’re not all created equal. Many synthetic supplements can lead to toxicity and imbalances in the body, while food-based nutrients—like those found in our CycleBites—work in harmony with your body for optimal absorption and safety. This is why we carefully choose real food ingredients for our products. Let’s dive into the risks of supplement toxicity, the differences between synthetic and food-based nutrients, and why whole-food solutions are the best choice for long-term wellness.

Understanding Supplement Toxicity

Supplement toxicity occurs when excessive amounts of a nutrient accumulate in the body, leading to harmful effects. Unlike nutrients from whole foods, which are naturally balanced with cofactors and fiber to regulate absorption, synthetic supplements often deliver high doses that bypass natural regulatory mechanisms.

Some of the most common nutrients associated with toxicity include:

  • Vitamin A: Excessive intake, especially from synthetic retinol (found in many multivitamins), can lead to liver damage, birth defects, and osteoporosis. The tolerable upper intake level (UL) for adults is 3,000 mcg (10,000 IU) per day. In contrast, beta-carotene from foods like carrots and sweet potatoes is converted to vitamin A as needed, reducing toxicity risk (Tanumihardjo, 2013).

  • Iron: While essential for oxygen transport, high doses of supplemental iron can cause oxidative stress, gastrointestinal distress, and increased risk of chronic disease. The UL for iron in adults is 45 mg per day. Food sources like spinach and red meat provide iron with natural absorption regulators (Sidebotham et al., 2022).

  • Calcium: Excess calcium supplementation has been linked to kidney stones and cardiovascular issues. The UL for adults is 2,500 mg per day for those under 50 and 2,000 mg per day for those over 50. Dietary sources like leafy greens provide calcium in balance with magnesium and vitamin K2, which help direct it to bones rather than arteries (Reid et al., 2011).

Why Food-Based Nutrients Are Better

Many supplements are synthesized in laboratories to mimic natural vitamins and minerals, but they may not have the same bioavailability or safety profile as nutrients from whole foods. Here’s why food-based nutrients, like those in our Cycle Bites, are the smarter choice:

  1. Better Absorption & Utilization: Synthetic forms of vitamins may not be as well-absorbed or utilized by the body. For example, folic acid, the synthetic form of folate, requires conversion in the liver, whereas natural folate from leafy greens is immediately usable (Bailey et al., 2010).

  2. Balanced with Cofactors: Whole foods contain additional phytonutrients, enzymes, and fiber that enhance nutrient absorption and function. For instance, vitamin C from citrus fruits comes with bioflavonoids that boost its effectiveness, whereas synthetic ascorbic acid lacks these cofactors (Carr & Vissers, 2013).

  3. Lower Risk of Imbalance & Toxicity: High-dose synthetic supplements can create imbalances. Excess vitamin E supplementation, for instance, has been linked to increased mortality, while dietary sources do not carry the same risk. The UL for vitamin E is 1,000 mg per day for adults (Miller et al., 2005).

How to Make Safer Choices

While some individuals may require supplements—such as pregnant women, older adults, or those with deficiencies—the safest approach is to prioritize nutrient-dense foods and use supplements judiciously. Here are some strategies:

  • Choose Whole Foods First: Prioritize a diet rich in colorful vegetables, whole grains, healthy fats, and lean proteins to naturally meet nutrient needs.

  • Opt for Food-Based Supplements: If supplementation is necessary, choose whole-food-based options like Funk It Wellness’ CycleBites, which contain naturally occurring vitamins and minerals in a balanced form.

  • Avoid Mega-Dosing: Stick to recommended daily allowances unless advised by a healthcare professional.

  • Monitor Blood Levels: Get lab tests when supplementing with fat-soluble vitamins (A, D, E, K) and minerals like iron to avoid toxicity.

  • Listen to Your Body & Consult Your Doctor: Every person’s nutritional needs are different. Always check in with your healthcare provider before making significant changes to your supplement routine, and pay attention to how your body responds.

Conclusion

At Funk It Wellness, we stand by the power of food-based nutrition. Supplements can play a role in health, but they are not a substitute for a well-balanced diet. Synthetic nutrients may carry risks of toxicity when taken in excess, while whole foods provide a safer, more effective way to obtain essential nutrients. By making informed choices, listening to your body, and consulting with your doctor, you can support your health naturally and sustainably—just like we do with our CycleBites!

References

  • Bailey, R. L., et al. (2010). "Folate: The underappreciated role of food fortification in the U.S. population’s folate status." The American Journal of Clinical Nutrition.

  • Carr, A. C., & Vissers, M. C. (2013). "Synthetic or food-derived vitamin C—are they equally bioavailable?" Nutrients.

  • Miller, E. R., et al. (2005). "Meta-analysis: High-dosage vitamin E supplementation may increase all-cause mortality." Annals of Internal Medicine.

  • Reid, I. R., et al. (2011). "Calcium supplements: benefits and risks." Journal of Bone and Mineral Research.

  • Sidebotham, E. L., et al. (2022). "Iron overload and chronic disease risk." Nutrients.

Tanumihardjo, S. A. (2013). "Vitamin A and bone health: The balancing act." The Journal of Clinical Endocrinology & Metabolism.

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