Lately, fructose bashing seems to be en vogue, an chic as saturated fat bashing has been (and still is) in the past. You have no idea how many clients come to me and tell me that one doctor or dietitian or another told them to stop eating ALL forms of sugar including fruit. The problem with that “restriction” is that these same practitioners are instructing them to eat lots of whole grains and polyunsaturated fats. This combination has a direct correlation to the storage of fat and insulin resistance due to the fact that whole grains (starch) break down into glucose directly and polyunsaturated fats ( mainly from nuts and nut oils, seeds and seed oils, grains and even beans that oxidize quickly and often are rancid even before eating them) blocks the ability of the cells to absorb these sugars keeping glucose outside the cells and circulating in the bloodstream, which is, in a sense, a “diabetic” state. Those sugars generally get sent to be stored as FAT.
I don’t make the rules. That bowl of cereal you are eating for breakfast is probably going to your thighs much more than that big bowl of strawberries you had in front of the TV last night.
So why is fructose so maligned? First, most of the “experts” are not clarifying that the fructose they are referring to is concentrated fructose such as HFCS (High Fructose Corn Syrup) and concentrated (and isolated) fructose, such as the crystallized fructose that is marketed as “safe for diabetics”, and agave syrup which is, in fact, refined by taking the agave glucose and inulin found in the plant’s roots and subjected to a chemical enzymatic process that converts it into nearly pure fructose. Agave syrup is about 70% (or higher) fructose whereby HFCS is actually only about 55% (but its formulation contains 80% additional ingredients that have, thus far, been “unidentified”). It bears saying that HFCS contains between 4 and 5 times the number of calories of pure sucrose which is nearly equal ratios of fructose to glucose.
Where fructose becomes problematic is the sheer volume of fructose (especially from concentrated sources such as HFCS and Agave), about 55 grams per day for the average adult and a whopping 73 grams for teens is problematic. Fructose is metabolized by the liver. As with all “sugar” not utilized for energy, fructose can be stored as fat but this fat is a bad fat called triglycerides. This is the visceral fat that can collect around organs and cause belly fat which raises the incidence of heart attack and stroke. It also breaks down into uric acid (think gout and kidney stones) and free radicals. That’s a lot of fructose (and glucose) running around in the body and, let’s face it, we just aren’t running long distances after buffalo any longer. There is no way to break down that kind of sugar, be it glucose or fructose, in the body unless, perhaps, you run several marathons a day. The ratios being skewed by more than 50-50 in favor of fructose (again and especially combined with some very questionable chemical ingredients) are also, I am sure, causing other negative chemical reactions.
Considering in the early 1900’s we took in only about 15 grams of fructose per day, mostly from fruits and vegetables and it is only today that we are seeing an epidemic of obesity, diabetes, and non-alcoholic fatty liver disease (in younger and younger patients, no less), it doesn’t actually surprise me that alarm bells are going off all around about the dangers of fructose. The problem is, as is the norm in our society, we take every new piece of nutrition related research (usually out of context) and chew it until there is absolutely no flavor left and spin it so that we cut out an entire food group not only unnecessarily but to the detriment of our health.
Remember:: Glucose is your body’s preferred and primary energy source. It is also responsible for the conversion of the thyroid hormone T4 (inactive) to T3 (active). The body simply cannot operate efficiently without glucose. I don’t care what the NO carbers say! Your body NEEDS carbs, but it needs efficient sources. It needs fruits (and vegetables) rather than starches (this means grains, whole or refined!!!).
Fructose, biochemically, has desirable effects on blood sugar and insulin sensitivity. It also inhibits the release of insulin by glucose making it pro-metabolic. Eating fruit, therefore, in place of starches, is actually a way of raising your metabolic rate and reducing the tendency to store fat. Fructose is also responsible for retaining copper, magnesium and calcium; very important minerals in the body. Again, we are talking about the fructose in fruits and vegetables, not in HFCS or Agave.
Fruits and their juices help calm adrenal glands making it easier for the body to handle stress. Two of the most common cravings with adrenal insufficiency is the “sweet” taste and the “salty” taste. There are reasons for this. The body is crying out for the sweet taste because it wants fruit to help calm the adrenals. The body cries for salt because it instinctively knows salt will help balance aldosterone levels (responsible for mineral and electrolyte balance) and encourage the thyroid to convert T4 to T3.
Take orange juice, for example. Fresh orange juice contains the ideal ratio of glucose to fructose. The same orange juice is also high in the minerals magnesium and potassium along with Vitamin C. This orange juice is pro-thyroid and helps lower stress hormones in the body due to the positive effects of high magnesium on the thyroid. Because of its optimal ratio of glucose to fructose it does not excite an inflammatory response or an oxidative state in the body. Add in 1/4 tsp. of Celtic Sea Salt and you lower stress hormones while balancing blood sugar to normal rates. Fructose (right along with sucrose, incidentally) increases glucouronic acid which is responsible for bonding with toxins and eliminating them from the body.
It might shock you to know that raw honey (unheated and preferably unprocessed) is a mix of fructose and glucose. It can increase metabolic rate!
Most fruits are also high in salycilates (think aspirin), which are enormously anti-inflammatory. The same CANNOT be said of grains which are pro-inflammation. Fruits, especially when eaten with nutrient dense foods (think raw dairy, bone broth or meat on the bone, wild shellfish) can rejuvenate the metabolism and increase insulin sensitivity. Increasing insulin sensitivity is key in those with thyroid, adrenal, PCOS, menstrual, and estrogen dominance issues. It is also critical in treating obesity, insulin resistance and/or metabolic syndrome.
Remember how we keep saying polyunsaturated fats (PUFAs) block the ability of glucose to be absorbed into the cells? (We know this thanks to a BRILLIANT biochemist and endocrinologist, Ray Peat, who has to be, bar none, the smartest and bravest man alive to go against “the norm” and what traditional nutrition education teaches….and is my hero!) Fructose bypasses the inhibiting effects of fatty acids and helps the utilization of glucose by the cells. This increases insulin sensitivity!
Note:: The exceptions to the fruit juice being pro-metabolic are two. Grapefruit juice has estrogenic qualities which is problematic if you have estrogen dominance issues. Apple juice contains pectin which can feed bowel bacteria (indeed candida). I do advise some of my clients to eat apples but whole rather than juiced and with proteins.
We are going to be talking more about sugar, its role in the body, and what carb cravings really mean tomorrow. Until then, eat that bowl of strawberries beckoning you from the fridge!