Vitamins, herbal medicines and other nutritional products may be more harmful than helpful to individuals with cancer. Check with an expert before taking them.
As an integrative medical physician who specializes in cancer, I see many patients who are extremely ill. In addition to recognizing the health benefits of proper nutrition, many suspect that supplements may help but don’t know how to safely or effectively administer them on their own. It is not uncommon for patients to come into my office with a shopping bag full of vitamins and other supplements they’ve purchased via infomercials, online or at local drugstores.
Seeing this happen over and over again concerns me, as many products aren’t what they claim to be. Because vitamins, herbs and natural supplements aren’t completely regulated by the Food and Drug Administration (FDA), many available over the counter (OTC) are of poor quality and, in some cases, more harmful than helpful.
When considering supplements to support health, a number of factors must be taken into account. First, just because a product is labeled “natural” doesn’t mean it’s safe or that the recommended dose is right for everyone.
The recommended daily intake of most vitamins and supplements is based on the needs of average healthy individuals in specific age and gender groups. Good health is a game of balance. Someone with nutrient deficiencies can experience signs and symptoms of fatigue; weakened immunity; changes in hair, nails and skin; poor cognition; or even bone loss. Excessive intake of nutrients, such as vitamin D, vitamin B6 and iron, can also cause problems, leading to side effects. Therefore, supplements should be dosed according to therapeutic intention and an individual’s specific needs found in bloodwork.
Second, mixing vitamins, supplements, medications and even foods, without knowledge about how they will react or interact, can be dangerous. Remember mixing baking soda and vinegar in science class, then waiting for the reaction? That scenario shows that even the most benign substances, when mixed, can create a strong chemical reaction.
For example, substances known as furanocoumarins in grapefruit and some other citrus fruits inhibit an enzyme called cytochrome p450 3A4, which is responsible for the metabolization of certain drugs. If taken within 24 hours of certain medications, including some chemotherapies and other cancer treatments, grapefruit juice can cause elevated blood levels of those drugs, making them much more potent than intended.
Next, timing of consumption should be considered. All vitamins, supplements and herbs have
a mechanism of action, a describable manner in which they work. For example, some supplements are anabolic. They have a buildup effect in cells to allow activities such as creating muscle or bone, which uses up energy.
Other supplements are catabolic. They have a breakdown effect, which releases energy to be used for body functions such as digestion. As a clinician, I find that patients get the most effective results when the supplements they combine have synergistic mechanisms of action.
Also, despite appealing product labels and clever marketing tactics, many products do not contain the high-quality ingredients they claim to. Although a regulatory standard called the Current Good Manufacturing Practice guides manufacturers on processing and labeling, the FDA does not review the safety or effectiveness of vitamins or supplements before they go to market.
A number of labs can measure quality, efficacy and safety, but many OTC supplements do not go undergo quality-control measures outside the companies that make and sell them. In addition to poor-quality ingredients, OTC products can contain various contaminants, artificial fillers, preservatives, heavy metals or other toxic agents.
Finally, it’s extremely important to use the best quality products available. Products made according to United States Pharmacopeia guidelines and labeled as such go through stringent quality-control measures to check their processing procedures and purity.
An agency other than the manufacturer must verify that all ingredients are at least 99% pure. Random samples are tested throughout the year to ensure that quality control and purity are maintained over time. Some of these products are available OTC, and some can be purchased at the offices of health care providers.
It’s easy to get overwhelmed when it comes to choosing supplements that are safe, effective and of high quality. I strongly recommend that anyone taking more than one multivitamin and one medication per day consult a natural medical provider who has extensive knowledge about vitamins, supplements and interactions in patients with cancer, as well as an oncologist, an oncology nurse or a cancer center pharmacist. Don’t let products that are supposed to optimize health cause more harm than good.