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How Diet and Supplements Affect Cancer

As a cancer specialist, I get asked nearly every day about nutritional supplements and the benefits they offer. Can they help control cancer? Do they reduce the risk of developing cancer? Can they help prevent other diseases and conditions? As it turns out, there is remarkably little useful data about the benefits of supplements. In fact, according to a recent article in Smithsonian Magazine, research has found that there are only five vitamins or supplements that are actually worth taking.

While the National Institutes of Health (NIH) devotes significant funding to researching nutrition and herbal medicine, there are few supplements that have been proven useful when it comes to cancer interventions. However, research suggests that certain dietary and supplement recommendations may help to prevent cancer and control the side effects of treatment.

How Diet Affects Cancer

It wasn’t until recently — since the mid 1900s — that humans have cut out the natural, unprocessed foods from our diet. Instead, we’ve replaced them with highly processed, packaged and even artificial foods that are calorie-dense but nutrient-poor. These foods may taste good, but in reality, they do little good for our bodies, especially if you have cancer.

In recent years, we’ve also switched from a diet where meat was a rarity to one where meat is present for breakfast, lunch and dinner. The dietary damage we have done to ourselves as a result of this change has led to obesity, poor impulse control among our youth, early onset heart disease and an increase in cancer diagnoses.

Additionally, Americans now consume the least amount of fiber ever in human history. This means that, when we eat, our glucose peaks faster and higher than ever before. The complexity of our food has decreased with the goal of instant carbohydrate satisfaction that lasts only a short time, leaving us desiring even more.

When it comes to preventing cancer, it is important to strive for a healthy and balanced diet that is rich in natural, plant-based foods. Diets such as the alkaline diet, ketogenic diet, low glycemic index diet, high-fiber diet, the Blue Zone diet and the Mediterranean diet are all centered on increasing the quantity of plant-based foods that we consume. Although there is no conclusive proof that links plant-based diets and cancer prevention, research does suggest that consuming more fruits and vegetables may be protective against certain types of cancers.

How Sugar Intake Affects Cancer

A plant-based diet is not the only factor that affects cancer prevention and control. When we are faced with treating endometrial, ovarian, breast or even colon cancers, sugar matters. More and more evidence is implicating sugar intake in tumor growth, tumor mutation and tumor resistance.

As a result of continued research in this area, increasing evidence is present to suggest that control of sugar intake matters. There are a number of clinical trials currently underway that are studying Metformin, a diabetes medicine, to help control blood sugar.

Dietary restrictions, controlled sugar intake and exercise can have a major impact on cancer prevention and control. In fact, studies are finding that dietary control and exercise in patients who have had endometrial cancer can reduce the risk of recurrence by 20 to 30 percent.

How Supplements Affect Cancer

So, what about supplements? Can they help to control or reduce the risk of cancer? While supplements are regulated by the FDA, they are not regulated in the same way that drugs are. Drugs need to be both safe and effective. Supplements, however, simply need to be moderately safe. In fact, many trials investigating supplements in high-risk persons for cancer have actually found an increase in cancer rates — the opposite of what we’d hope to find with a supplement.

Are there any safe supplements for cancer patients? Fish oil and vitamin D hold much promise but need to be studied more. The biggest concern with fish oil is simply the route of delivery. Swallowing a capsule does not provide the same benefits as actually eating fish. Simply put, supplements are not food. The chemicals absorb and act differently within the body when we purify, concentrate and put it in a capsule.

What about vitamin D? Low vitamin D is extremely common — even in the Sunshine State — and it is associated with ovarian cancer, breast cancer and many other health problems. The real question here is, “Why is it low in the first place?” Are individuals with low vitamin D simply sicker and more prone to health problems? The jury is still out.

In addition to fish oil and vitamin D, there are a few other supplements that may be beneficial. As many of my patients know, there are known benefits associated with vitamin B6, turmeric, green tea and even garlic, which can help reduce nausea caused by cancer treatment. Glutamine powder has also been shown to help with neuropathy, which is a common side effect of chemotherapy that affects the peripheral nerves and typically causes numbness or weakness.

It is important to talk with your doctor and pharmacist about herbs and supplements you are taking or considering taking. They may be regulated by the FDA, but remember, that doesn’t necessarily mean they are beneficial. As long as you focus on your diet and exercise, you will have a greater chance of preventing or controlling cancer.