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December 3, 2024 - Carbohydrate Nutrition News

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August 26, 2024 - Carbohydrate Nutrition News

New Fact Sheet: Types of Sugars and Sweeteners


Cancer

Cancer is a large group of diseases that starts when abnormal cells grow and divide uncontrollably (1, 2). 

  • Risk Factors for Developing Cancer. There are many risk factors for developing cancer; some cannot be controlled while others can be modified to reduce risk. 
  • Reducing Cancer Risk. Lifestyle factors that can help reduce risk of cancer include maintaining a healthy body weight, consuming a balanced diet, being physically active, and limiting alcohol intake. 
  • Sugars and Cancer. Evidence from systematic review and meta-analyses suggest an indirect link between sugars and cancer risk from sugar’s contribution to calorie intake. Consuming excessive calories, including calories from sugars, can increase the risk of overweight and obesity, which can then increase risk of some types of cancer. 
  • Sugars in the Diets of Individuals with Cancer. Dietary recommendations about sugars for individuals with cancer are not different from recommendations for individuals without cancer, with a focus on reducing intake of foods and beverages high in added sugars. 

Risk Factors for Developing Cancer

There are several factors that increase a person's risk of developing cancer. Some cannot be controlled while others can be modified to reduce risk. The Canadian Cancer Society and US National Cancer Institute (3, 4) identify the following risk factors for cancer:

Non-modifiable risk factors Modifiable risk factors
  • Age
  • Cancer-causing substances that may be in the air or drinking water (e.g. arsenic, formaldehyde)
  • Polluation
  • Specific inherited genes
  • Having a condition that suppresses the immune system
  • Chronic inflammation
  • Hormone levels 
  • Drinking excess alcohol
  • Smoking
  • Having an unhealthy diet
  • Low levels of physical activity
  • Having overweight or obesity 
  • Sun exposure
  • Exposure to radiation (e.g. radon, X-rays)

Reducing Cancer Risk

Obesity or excess body weight has been associated with an increased risk of many types of cancer. One lifestyle factor that can contribute to overweight and obesity is consuming excess Calories compared to daily requirements for normal body functions, movement, and physical activity. 

To reduce the risk of cancer, the Canadian Cancer Society (5) recommends: 

  • Living smoke-free
  • Protecting your skin and eyes from the sun 
  • Having a healthy body weight 
  • Eating a healthy and balanced diet 
  • Being physically active
  • Limiting alcohol consumption 

The overall recommendation to maintain a healthy body weight includes the following dietary and lifestyle recommendations:

  • Following recommendations in Canada’s Food Guide to eat a well-balanced diet that includes a plenty of vegetables and fruit, whole grains, and fibre, with healthy fats and very few processed foods; 
  • Limiting consumption of red and processed meats, and foods and beverages high in sodium, saturated fat, and sugars; 
  • Drinking mostly water rather than sugars-sweetened beverages; and
  • Being physically active 

Sugars and Cancer

Does consuming sugars feed the growth of cancer cells? According to the Canadian Cancer Society, while every cell in the body uses sugars in the form of glucose as a source of energy, eating sugars “does not make cancer cells grow faster” (6). There is also a lack of evidence that limiting sugars intake can “starve” cancer cells or lowers the risk of getting cancer (7). 

Evidence from systematic reviews and meta-analyses does suggest that: 

  • There may be an indirect link between sugars and cancer through sugar’s contribution to calorie intake. i.e. foods higher in calories may be higher in sugars -> consuming high calorie foods on a regular basis may lead to weight gain -> weight gain is associated with an increased risk for some types of cancers (7-9).
  • There is a correlation between drinking sugars-sweetened beverages and increased risk of some cancers (10,11).

In addition to Calories, the presence of other factors including micronutrients and fibres in sugars-containing foods may influence the association with cancer risk. Dietary fibres and certain micronutrients such as folate, vitamin C, selenium and carotenoids have been shown to be protective against cancer development (12). 

National and international agencies recommend: 

  • Limiting consumption of sugar-sweetened drinks; 
  • Avoiding high-calorie foods and drinks; and 
  • Limiting consumption of fast foods and other processed foods high in fat, starches, or sugar (7-8, 13-14).

Sugars in the Diets of Individuals with Cancer 

The idea that “sugar feeds cancer” is a common misconception in the media. Sugars per se do not have a direct link to cancer. 

Many healthy foods, including whole grains, cereals, fruits, and dairy products, naturally contain sugars, along with vitamins, minerals, fibre, and other nutrients. Dietary recommendations about sugars for individuals with cancer are not different from recommendations for individuals without cancer (11). 

Recommendations include:  

  • While avoiding sugars is not necessary, it is best to consume most of sugars from naturally occurring sources and nutrient-dense sources, such as vegetables, fruits, plain dairy, and whole grains. 
  • Limit the amount of added sugars in the diet by reducing portion sizes of desserts and sweets, reducing intake of processed foods high in added sugars and limiting sugars-sweetened beverages. 

For more information, additional resources include:

Recent news items include:
References
  1. Canadian Cancer Society. What is Cancer? [Internet]. Canadian Cancer Society; 2024 [cited 2024 Mar 20]. 
  2. World Health Organization. Cancer [Internet]. World Health Organization; 2024 [cited 2024 Mar 11].
  3. Canadian Cancer Society. What Causes Cancer? [Internet]. Canadian Cancer Society; 2024 [cited 2024 Mar 1]. 
  4. National Cancer Institute. Risk Factors for cancer [Internet]. National Cancer Institute; 2015 Dec 23 [cited 2024 Mar 1].
  5. Canadian Cancer Society. Reduce Your Risk [Internet]. Canadian Cancer Society; 2024 [cited 2024 Mar 20].
  6. Canadian Cancer Society. What’s the Link Between Sugar and Cancer? [Internet]. Canadian Cancer Society; 2024 [cited 2024 Mar 20]. 
  7. Cancer Research UK. Sugar and Cancer – What You Need to Know [Internet]. Cancer Research UK; 2023 Aug 16 [cited 2024 Mar 20].
  8. Canadian Cancer Society. The Health Costs of a Sweet Tooth [Internet]. Canadian Cancer Society; 2024 [cited 2024 Mar 20].
  9. Makarem N, Bandera EV, Nicholson JM, Parekh N. Consumption of Sugars, Sugary Foods, and Sugary Beverages in Relation to Cancer Risk: A Systematic Review of Longitudinal Studies. Annual review of nutrition. 2018 May 25(0). 
  10. Jatho A, Myung SK, Kim J, Han SS, Kim SY, Ju W. Consumption of sugar-sweetened soft drinks and risk of gastrointestinal cancer: A systematic review and meta-analysis of observation studies. Oncology. 2024;102(2):141-56.
  11. Feng L, Gao J, Xia W, Li Y, Lowe S, Yau V, Ma S, Zhou Z, Ding P, Cheng C, Bentley R, Wang Y, Zhou Q, Wang K, Birong W, Xie P, Liu H, Sun C. Association of sugar-sweetened beverages with the risk of colorectal cancer: a systematic review and meta-analysis. Eur J Clin Nutr. 2023 Oct;77(10):941-52.
  12. Willett WC. Micronutrients and Cancer risk. Am J Clin Nutr. 1994;59:1162S-1165S. 
  13. BC Cancer. Sugar and Cancer [Internet]. BC Cancer; 2023 Oct 2 [cited 2024 Mar 20].
  14. World Cancer Research Fund. Cancer Prevention Recommendations [Internet]. World Cancer Research Fund; 2018 [cited 2024 Mar 20].