Part 2: Does Sugar Feed Cancer?

Part 2: Does Sugar Feed Cancer?

Does Sugar Feed Cancer In Part 1 of my Does Sugar Feed Cancer? series exploring the connection between sugar and cancer, I answered the questions What is one connection between sugar and cancer? And should I be on a Ketogenic diet? To find out the answers to these questions and learn how you can take action to reduce your cancer risk, read Part 1 here.

In Part 2, I will continue to explore the relationship between sugar and cancer to help guide you in understanding how your food choices can impact your cancer risk. I believe there are incremental changes you can make in your diet and lifestyle that will reduce your risk of developing cancer. These changes work through a variety of channels including supporting your immune system, reducing chronic inflammation and acting on cancer cells directly.

I want you to understand these channels because I think this will lead to greater appreciation for the power that food has on cancer risk. These changes that you can make will also boost your overall health and vitality, while allowing you to overcome your fear and thrive after cancer. To join a group of cancer thrivers who meet regularly to learn more about this topic and get support with their food and lifestyle goals, you are invited to join my Thriving After Cancer Coaching and Support Program by following this link.


In today’s blog, I will explore the Insulin and Diabetes Connection to Cancer…

  • How are diabetes and cancer connected?
  • How are insulin levels connected to cancer?
  • Which cancers have insulin receptors?
  • How do I use this information to reduce my risk?
Diabetes and Cancer

Are these two seemingly different conditions related? According to the author of several papers on the connection, having diabetes will put a person at higher risk of developing certain cancers. These are cancers of the liver, pancreas, kidney, endometrium, colon or rectum, bladder, non-Hodgkin’s lymphoma and breast.

What is Responsible for the Increased Cancer Risk in People with Diabetes?

Diabetes provides two crucial elements that help to initiate cancer and keep it progressing and those are; high blood sugar levels and high insulin levels. The mechanism that seems to be the biggest driver of cancer growth is high insulin levels.

High Insulin Levels

This condition is called hyperinsulinemia (hyper=higher and emia= in the blood). What is the mechanism in which higher than normal levels of insulin promotes cancer? There are three mechanisms postulated and these are;

  1. Firstly, insulin will cause a decrease in insulin-like growth factor (IGF-1) binding proteins. IGF-1 is a growth promoter, when its binding protein is kept busy by insulin it is free to circulate in the bloodstream at higher levels. This results in more IGF-1 available to promote the growth of cancer cells.
  2. Secondly, cancer cells have a greater number of insulin receptors. Insulin will dock into these receptors (like parking places) and this docking triggers the cells to undergo mitosis. Mitosis is the process of cell division in which a parent cell replaces itself with two identical daughter cells. This process is growing the cancer.
  3. Third and finally, higher levels of insulin. This is a hallmark of both prediabetes and type 2 diabetes and results from a condition called insulin resistance. When your body’s normal cells are resistant to insulin, this creates higher than normal insulin levels and this insulin can then find its way to insulin receptors on cancer cells. When insulin docks onto cancer cells it amps up cell division, putting this process into hyper drive and causing the cancers to grow rapidly.
Which Cancers Have Insulin Receptors?

Researchers from the University of Magna Craecia of Catanzaro, Italy have published a thorough review of the connection between insulin receptors and cancer progression (2).

According to their summary, the following cancers have insulin receptors:

  • Breast
  • Thyroid
  • Colon
  • Ovarian
  • Prostate
  • Sarcomas
What Does This Mean For Me as A Cancer Thriver?

Does Sugar Feed CancerThere are several action steps you can take that will help you benefit from this information.

  1. If you have type 2 diabetes and are taking medication for it, you should know that some diabetes medication works by making your body produce more insulin. For example, the sulfonylureas would increase insulin. In contrast metformin and thiazolidinediones decrease insulin levels. If you currently have type 2 diabetes and want to decrease your cancer risk, talk to your doctor about using metformin as your treatment of choice.
  1. Excess body fat leads to more insulin resistance. To reverse this and improve the insulin sensitivity of your cells, begin a weight loss program that includes a healthy balanced diet combined with regular moderate exercise.
  1. To achieve better control of blood sugars and insulin follow an eating plan that minimizes spikes in your blood sugar level. This means eating a diabetic diet even if you don’t have diabetes. This would be an eating plan that includes:

Minimizing sweets like soda pop, candies and added sugars

Choosing more whole grains (these are also called low glycemic) instead of refined and processed carbohydrate (called high glycemic). For example, choose whole grain bread over white bread, choose brown rice over white and choose whole flours for baking and not all purpose flour

Choosing fruits and vegetables over juice

Balancing your meals and snacks with a protein and carbohydrate choice. For example, instead of a fruit at snack combine a fruit with some nuts.

  1. You can make your cells more sensitive to insulin (less resistant) by regular moderate exercise.


What You Eat Matters

I firmly believe that what you eat matters. This is more proof that if you eat in a way that balances your blood sugars and minimizes insulin resistance, you can help protect yourself from the cancer promoting effects of elevated insulin levels.

Stay Tuned for More on Sugar and Cancer

In my next blog, I will help you understand the connection from sugar to visceral fat to cancer. This is important information that you need to help you understand how changing your diet is a powerful tool in your goal to be cancer free.

What Stakeholders Say

Oncology Dietitians – “Much research shows that it is sugar’s relationship to higher insulin levels and related growth factors that may influence cancer cell growth the most…”

Join the Conversation

Do you have diabetes or elevated insulin levels? What are you doing to reduce your risk? Let our community know in the comments section below!



Diabetes and Cancer. Vigneri P1, Frasca F, Sciacca L, et al. Endocr Relat Cancer. 2009 Dec;16(4):1103-23.
Insulin receptor and cancer. Belfiore A and Malaguarnera R. Endocr Relat Cancer. 2011 Jul 4;18(4):R125-47.
Diabetes and cancer: is diabetes causally related to cancer? Suh S, Kim KW
Diabetes Metab J. 2011 Jun;35(3):193-8.