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Fruit Isn’t All That!

This article draws heavily from great work on carbohydrate metabolism by Dr. Gary Fettke, a Tazmanian surgeon who drew the ire of the nutritional service at his hospitals when he suggested diabetic patients could prevent further amputations if they lowered their carbohydrate intake. Even though the government guidelines suggest you should get half your calories from fruits and grains, excessive carbohydrate intake is dangerous. For millenium carbohydrate intake was seasonal and fruit based and since we began to bake and use grains our health has deteriorated. Fruit was intended to fatten us up for Winter. We now have endless Summer in our groceries so we are not seasonal anymore and it shows in our waistlines.

All carbohydrates are sugar. There are many different sugars…glucose, sucrose, fructose for example. The human body goes to great lengths to remove excess sugar from the bloodstream. Any excess sugar in the bloodstream is dealt with aggressively by the body to keep the levels low because too much is toxic. Turns out more than a teaspoon of sugar has a toxic effect.

It’s all about energy production and that brings up the Krebs cycle in which acetyl coA is converted by the mitochondria into energy…ATP to be exact. Acetyl coA can be produced from fatty acids, sugar and amino acids. There is no absolute need for sugar as an energy source in contrast to fatty acids and amino acids which are absolutely essential.

Glucose can be consumed by us or created by gluconeogenesis and from glycogen stores.

Excess glucose triggers an elevation of sugar which in turn stimulates insulin. More than one teaspoon calls for a response. A slice of bread contains 5 teaspoons of sugar so that’s a lot of extra sugar that the body has to remove from circulation. Glucose and fructose are very similar sugars but are handled very differently by the body. Fruits contain both glucose and fructose in roughly even proportions.

Chronic elevation of sugar causes advanced glycogenated end products to build up. This turns to oxidized fats etc. to contribute to inflammation. These AGE’s affect the brain, the eyes, the heart, the kidneys, wound healing, infection and cancer. Elevated glucose levels also glycate other tissues and lipids. The glycocalyx is a coating of every endothelial blood vessel…it’s critical to health and is fragile. This organ of sorts is particularly affected by elevated blood glucose. Damaging the glycocalyx is analogous to damaging the lining of your gut causing leaky blood vessels much as you get a leaky gut .

Excess sugar triggers increased insulin which is generally inflammatory. There is a direct correlation between insulin levels and degree of inflammatory markers in the knee as shown in a study done within the last 5 years and mentioned by Dr. Fettke.

Insulin reduces vitamin D absorption; Insulin stimulates tumor growth; Insulin lowers magnesium levels which are required in myriad biochemical pathways and insulin increases clotting measures.

Now Fructose in particular is mostly metabolized in the liver. Fructose raises uric acid which is also inflammatory and elevated uric acid negatively affects the production of nitric acid which is a critical component of vascular heath. Uric acid decreases white cell function and adversely affects our response to infection. Fructose actually increases hunger via both the leptin and ghrelin pathways if you want to get technical. Fructose increases the oxidation of LDL, the type of lipid your doctor calls the “the bad cholesterol.“

Just as an aside…why do they give you so much sugar in the hospital? It’s not just in the food…breakfast pizza and pecan pie are touted as healthy. Sugar is directly toxic to the immune system but how many people are getting a sugar water intravenous solution?! One more thing to worry about when you go into the hospital.

One way to manage your sugars is obviously via your diet. Keto diets are low carbohydrate/low sugar diets that directly address this issue of carbohydrate toxicity. Many physicians are leery of a keto diet but let’s look at the keto diet in the most vulnerable population we have…unborn babies. We have a long and consistent medical record here. Mothers with morning sickness are often in ketosis…this is something we have seen and measured. The other end of the spectrum is babies whose mothers have gestational diabetes. So. Some babies are exposed to very low sugar and some babies are exposed to high sugar levels and we can track their outcomes. It’s no surprise that the keto exposed babies are healthier in every metric compared to the gestational diabetes babies…premature births, birth defects etc…all worse in the high sugar group.

Scheduled obesity is the process of turning sugar into fat during times of plenty. There were papers published as early as 1948 that connected sugar with illness. By 1992 the food guide suggested 5-9 fruits and vegetables a day but there is no real science behind that recommendation. In 2005 the CDC partnered with the produce industry to continue to promote fruits along with vegetables. The Epic Study in Europe involved over 500,000 people and lasted for over 15 years and did not show a correlation between fruits and veggies and cancer rate.

How much sugar is healthy according to the World Health Organization? 25 grams which is 6 teaspoons of sugar a day. We have gone from 5 pounds a year of sugar consumption to 152 pounds a year. And that’s an average.

Well, what about all the other nutritional benefits of fruit in terms of minerals, vitamins and micronutrients? Fruit nutritional value is overstated. Look at antioxidants…a cup of coffee has much more antioxidants than most fruits. Look at vitamins…well green leafy veggies have much more vitamin E, vitamin A etc. Look at minerals…again green leafy veggies, ie. spinach, has more potassium than the banana. Fruit also has less phytonutrients and fiber than many vegetables.

So let’s start the New Year off right and keep things in perspective. Fruit may not be the substance you should base your diet on but it’s way healthier than any fast food, fried food, processed food and liquid calories like soda and fruit drinks. Have fruit but seasonally and sporadically like your ancestors experienced and see how you feel. If you want to try to lower your carbohydrates in your diet, I would refer you to Keto Syracuse on facebook. Keto Phil knows what he is talking about and has all the references you would ever want and more.

Knowledge is power. Make this the year you become truly powerful! Until next month…get well and stay well.

Dr. Barry