Actor Ashton Kutcher recently disclosed health issues brought on by following an all-fruit diet,1 adopted in preparation to play the character of Steve Jobs in the upcoming film “Jobs,” due out April 19. “First of all, the fruitarian diet can lead to like severe issues. I went to the hospital like two days before we started shooting the movie. I was like doubled over in pain. My pancreas levels were completely out of whack. It was really terrifying … considering everything.” The “everything” is likely a reference to pancreatic cancer. Even though Jobs consumed a fruitarian diet years before he contracted his pancreatic cancer, there could be some relationship.
Fructose, a simple sugar found in fruit, is preferentially metabolized to fat in your liver, and eating large amounts has been linked to negative metabolic and endocrine effects. So eating very large amounts – or worse, nothing but fruit– can logically increase your risk of a number of health conditions, from insulin and leptin resistance to cancer. Research has shown that pancreatic tumor cells use fructose, specifically, to divide and proliferate, thus speeding up the growth and spread of the cancer. Pancreatic cancer is one of the faster spreading cancers; only about four percent of patients can expect to survive five years after their diagnosis.
Your pancreas contains two types of glands: exocrine glands that produce enzymes that break down fats and proteins, and endocrine glands that make hormones like insulin that regulate sugar in your blood. Steve Jobs died of tumors originating in the endocrine glands, which are among the rarer forms of pancreatic cancer. Insulin production is one of your pancreas’ main functions, used by your body to process blood sugar, and, in the laboratory, insulin promotes the growth of pancreatic cancer cells. There’s reasonable cause to suspect that if your body maintains high levels of insulin, you increase the pancreatic cancer’s ability to survive and grow. In fact, researchers now believe that up to a third of all types of cancers may be caused by diet and lifestyle. So if you want to prevent cancer, or want to treat cancer, it is imperative that you keep your insulin levels as low as possible.
Tumor cells do thrive on glucose and do not possess the metabolic machinery to burn fat. However, the cells used fructose for cell division, speeding up the growth and spread of the cancer. Think of this the next time you drink that can of soda containing high fructose corn syrup. Eliminating processed foods, candy and soda with high fructose corn syrup, and replacing it with an all-fruit diet is likely not going to improve your health. Many tend to believe that as long as fruit is natural and raw they can have unlimited quantities without experiencing any adverse metabolic effects. It’s important to consider ALL sources of fructose, and to try to limit your total consumption if you want to optimize your health (15-25 grams/day).