New Year’s Resolutions: Tips for a healthier 2025

Myth: Eliminating sugar starves cancer cells

A common misconception is that “sugar feeds cancer”, so you should eliminate it from your diet. While “sugar feeds cancer” is technically true, it is oversimplified. Cancer cells, just like all cells in our body, primarily use glucose for energy, which mainly comes from carbohydrates in our diet. Although cancer cells tend to consume more glucose than normal cells, cutting out sugar or carbs will not get rid of glucose in our bodies. Your body converts fats and proteins into glucose and other useful energy sources to keep you alive. Additionally, cutting out carbohydrates also takes away many healthy, protective foods from our diet. Glucose is our most important energy source, and there is no way for your body to stop glucose from being used in cancer cells while making sure your healthy cells are unaffected.

The relationship between sugar, carbohydrates, and cancer is extremely complex. Firstly, it’s important to understand the difference between added sugars and natural sugars. Natural sugars are found in foods such as fruits, vegetables, and dairy products. While relatively high in sugar, these foods also contain fibre, water, and essential nutrients that are protective against cancer. Added sugars, such as those found in sugary beverages, desserts, and candy, can lead to obesity, inflammation, and insulin resistance, all of which are linked to increased cancer risk.(2) This also applies to carbohydrates. While high-carbohydrate diets can lead to obesity and inflammation, eating whole grains or pairing your carbohydrates with protein and fibre helps stabilize blood sugar and insulin levels, and can be protective against cancer. A great example of this is the Mediterranean Diet. It is associated with a lower risk of several types of cancer and cancer mortality, which is mainly attributed to the higher intakes of fruits, vegetables, and whole grains.(3) The relationship between sugar, carbohydrates, and cancer is not straightforward. It’s important to consider your overall dietary patterns and lifestyle factors.

The bottom line: You don’t need to cut out all sugar and carbohydrates if you have cancer. Instead, focus on eating a diet rich in whole grains, fruits, vegetables, healthy fats and adequate protein.

If you are interested in reading more on this topic, check out this blog (https://integrativeonc.org/latest-news/does-sugar-feed-cancer/) from the Society of Integrative Oncology that goes into much more detail about sugar and cancer.  

Myth: Fasting starves cancer cells

Tying into the above myth, this one is broader and suggests that depriving the body of all food will deprive cancer cells of energy and they will die off. Starving yourself will not kill cancer cells and is very dangerous. Just as our bodies can create glucose from other dietary sources, it can also create glucose from its own cells. When we fast for long periods of time, the body breaks down its own fat stores and muscle to create energy and keep us alive and functioning. Fasting for long periods can be dangerous for healthy individuals, but for those with cancer, maintaining weight (especially muscle mass) is very important.

The bottom line: Do not starve yourself. Ensure you maintain a healthy weight and eat a sufficient amount of protein, especially if you are getting cancer treatments.

Small caveat: There is some evidence that fasting for short periods can aid in cancer treatment and help manage side effects.(4) Research is not conclusive on this topic, and you should speak with a healthcare provider if you are interested in hearing more.

Myth: Juicing is essential for cancer prevention and treatment

There is no evidence that an all-juice diet prevents cancer or affects cancer cells in any way. Juicing produces foods that are high in calories and sugars while being low in protein, fibre, and fat. While you may be eating “natural” sugars, one of the most important aspects of whole fruits and vegetables is fibre, which is reduced in the juicing process. As mentioned earlier, higher fibre intake is associated with reduced risk of several cancers. Combined with a lack of protein and fat, purely juice diets can be especially dangerous for people receiving cancer treatments who need these important nutrients. Homemade juicing is certainly better than drinking sugar-sweetened juice, and it’s a great way to get concentrated nutrients and hydration, but it should not replace a balanced diet.

The bottom line: Use juicing to complement, not replace, a balanced diet rich in whole foods, fibre, protein, and healthy fats.