Whole Health for a Whole Life | LifeScape

The Dose Makes the Poison

Written by Dr. Susan Wilder | Jun 9, 2022 7:22:22 PM

The Dose Makes the Poison

One of my daughters, when little, used to say, “if at first you don’t exceed, try try again!” A unique American flaw is the tendency to overdo – whether with food, alcohol, drugs, stress, and even exercise. If some is good, more must be better. However, when it comes to supplements, protein, and even water, overdosing can be as hazardous as a deficiency.

Many of us collect what I call my “medicine cabinet hall of shame” – the pills, potions, and cosmetic concoctions promising a quick fix to some compelling challenge. However, we all know that the best answers to optimal health do not come from a bottle.

Some of the nutrients with toxic risk in excess include:

  • Vitamin D: Your concierge lab panels include this level because it has a very narrow “Goldilock’s" zone. The most recent evidence has down-shifted the optimal level of 20-40 associated with the lowest risk of all-cause mortality, covid mortality, cardiac risk, cancer risk, and fractures.  Excess can result in calcium deposits, kidney stones or kidney injury, nausea and vomiting, and overall reduced bone density.

  • Protein: Excess protein will be stored as fat like any other excess nutrient. Excess protein can also directly harm kidneys. Getting enough is critical but beware of large animal protein servings (use the palm of your hand as the best guide to serving size), and all the powders, bars, and collagen supplements that might push you over the edge. Work with Dana or your provider on calculating your protein needs and divide it throughout the day.  Calculators can also help guide protein intake.

  • Vitamin B6/pyridoxine: Those with common genetic methylation defects can easily develop a toxic build-up of B6 (cause of neuropathy) and homocysteine (increasing clot and heart risk). In supplements, look for the P5P form of B6.

  • Calcium: Food is always the best delivery system for calcium. Calcium supplements flood the body with a massive load of calcium while foods rich in calcium parse it out gradually. Calcium supplements should only be taken if unable to get enough through food. Anyone with aortic stenosis should avoid calcium supplements.

  • Iron: No one should be taking iron without proven deficiency or clinical reason. Excess is toxic to the heart, liver, and joints. Those with any family history of iron overload should have iron levels and genetic testing for hemochromatosis. Alcohol also impedes liver clearance of iron and other toxins.

  • Iodine: Although critical to thyroid function, excess iodine can actually harm the thyroid, increasing the risk of autoimmune thyroiditis or hypothyroidism. Iodine supplements or even iodized salt should only be taken by those with specific nutritional needs.

  • Vitamin A: Fat-soluble vitamins (A, D, E, and K) can accumulate in fatty tissues and become toxic. Avoid doses over 10,000iu/day and n pregnancy as it can cause birth defects.

  • Vitamin E tocopherols/Beta-carotene: Rarely does anyone test deficient in vitamin E. Excess in the tocopherol form can cause bleeding risk. Although thought to be beneficial antioxidants, evidence is conflicting including increased risk of lung cancer and more aggressive prostate cancer in those supplementing with Beta carotene or tocopherols. Tocotrienol forms look more promising at this time with beneficial effects on cholesterol, apoB, and blood sugar.

  • Omega 3 Fish Oil:  Most of us are deficient in anti-inflammatory omega 3 fats and over-consume inflammatory omega 6 fats (in processed foods like crackers, chips, snack foods, and salad dressings) so most need to boost omega 3 intakes through foods or supplements. Excess omega 3, and omega 6:3 ratio below 2 are associated with increased spontaneous bleeding risk.


Bottom line: Food is the best, most efficient, and safest delivery system for nutrients.

As Michael Pollan put it best, “Eat real food, mostly plants, not too much” and “if it’s delivered through the window of your car, it’s not food.”

Nutritional supplementation must be personalized, strategic, and carefully monitored.

Supporting a healthy gut lining and microbiome is key to nutrient utilization, immune health, toxin clearance, healthy hormone balance, and brain health.  

Join Healthy Kitchen, Healthy You Club, a virtual community guided by Dana, LifeScape’s Functional Dietitian, focused on blending the most recent scientific guidelines into the art of making real, whole, nourishing food with joy and ease.