But here is the inconvenient truth: supplements are not inherently good, bad, or magical. They are tools. And like any tool, they work best when you know exactly what you are fixing.
The human body is not a one-size-fits-all system. Yet many people supplement as if it were – adding vitamins and minerals “just in case,” stacking products based on trends rather than data and assuming more is better. This approach is not only inefficient – it can be counterproductive.
Before you click “buy,” pause. The smartest rule in supplementation is not trendy, it is timeless: Test, Don’t Guess. A simple blood-based micronutrient assessment reveals what your body truly needs – and just as importantly, what it does not. This matters because both deficiencies and excesses can impair health, particularly with fat-soluble vitamins like A, D, E, and K, the accumulations of which are easy to miss until damage is done.
In short: guessing can lead to expensive urine at best, and unintended consequences at worst.
Supplements are called supplements for a reason – they are meant to fill gaps, not replace food. When nutrients come from whole foods, they arrive packaged with fiber, fats, enzymes and phytonutrients that enhance absorption and utilisation.
Research consistently shows that nutrients consumed from food are associated with better health outcomes than the same nutrients taken in isolation. Translation: a spinach salad still beats a green pill.
Label claims
Supplement labels love big numbers. A tablet boasting 1,000 mg of vitamin C or 5,000 IU of vitamin D sounds impressive – but the body does not absorb nutrients based on label claims. It absorbs them based on biology.
When you swallow a supplement, it does not take a direct route to your cells. Instead, it moves through a series of digestive and metabolic steps collectively known as first-pass metabolism. After absorption in the gut, nutrients travel via the portal vein to the liver, where they may be metabolised, stored, converted to less active forms, or eliminated before reaching systemic circulation.
This is a safety mechanism, not a flaw – but it means the amount you ingest is never the amount your body actually absorbs, and also the reason many supplements simply become expensive urine.
First-pass metabolism helps explain why absorption is not linear. As doses increase, the percentage absorbed decreases. Vitamin C absorption drops sharply at higher doses. Calcium is best absorbed in amounts under 500 mg at a time. Magnesium absorption declines as intake rises.
While food delivers smaller quantities, it often results in higher proportional absorption. A modest dose absorbed at 50% can outperform a megadose absorbed at 5%. More milligrams do not mean more nutrition, just more for the liver to manage.
The body absorbs nutrients most efficiently when they arrive as part of whole foods, accompanied by their natural cofactors. For example, Iron + Vitamin C: Plant-based iron is absorbed far more efficiently with vitamin C. Think lentils with bell peppers, spinach with citrus dressing, black beans with fresh salsa, or oats topped with berries.
Calcium + Vitamin D + Magnesium: Vitamin D facilitates calcium transport and magnesium activates vitamin D – remove either, and calcium utilisation drops. Effective combinations include sardines or salmon with leafy greens, Greek yogurt with nuts or seeds, and tofu with broccoli.
When you do need a supplement, remember that fat-soluble vitamins need fat! Vitamins A, D, E and K require dietary fat. Taking vitamin D with orange juice (all carbs, no fat) significantly reduces absorption compared to taking it with foods containing fats, such as eggs, avocado, or olive oil.
Regulated
Unfortunately, supplements are not regulated like pharmaceuticals. Random testing of well-known brands has found products with incorrect dosages, contaminants, or ingredients that do not match the label. Only purchase supplements that have undergone independent third-party testing by groups such as USP, NSF International, or ConsumerLab. Products sold on hype rather than evidence are where mislabeling, contamination and ineffective dosing most often hide.
Here is what no supplement company wants you to know: your money is often better spent on nutrient-dense food. Whole foods like vegetables, legumes, eggs, oily fish, quality proteins, nuts, seeds and grains deliver nutrients in the form your body recognises best and knows how to metabolise.
Supplements can be useful – and sometimes essential – when deficiencies are confirmed or absorption is compromised. But they are not shortcuts around poor dietary habits.
Test, Don’t Guess. Supplement selectively. Pair intelligently. And remember – the most effective nutrient delivery system ever designed still comes from food.
Mother Nature remains undefeated.
Libby Heath recently became the first Mayo Clinic certified wellness coach in Asia. She shares her insights and advice through her column ‘Wellthwise’ here in The Phuket News. Please note that if you have a condition that requires medical treatment, consult your doctor. Contact Libby at: BeWellthwise@gmail.com.