Health Hack #17 - Not All Sugars Are Created Equal, either
In last week’s post (link here) we explained why all calories are not created equal. A vital part of that conversation relates to sugars: how they come in different shapes and forms, and how we metabolize them dependent upon their type. As we’ll learn here, not all sugars are created equal either, so it’s vital that we’re cognizant of which ones we consume. While the old adage of keeping your sugar intake at a minimum rings true and is endorsed by our Real Food philosophy, sugars exist across all spectrums of food - real food plants included - so it’s important to develop a context for what they are and where they’re found; otherwise you may not even realize the quantities with which you’re ingesting them. They are truly unavoidable, in most cases, but this is as nature intended. We should just learn to be careful of over-indulging, and be particularly cautious of certain types. Our aim here is to provide a basic framework for understanding the nuance of sugar, as it may help steer your future dietary choices.
We’ll be focusing on three different types of sugars: two that fall into the “simple sugar” category (aka “Monosaccharides”) and one that falls into the “compound sugar” category (aka “Disaccharides”). We’re honing in on these three because they’re the most abundant in the foods we encounter, both real and otherwise. Two of those that we’ll be excluding - Galactose and Maltose - do not arise in their free state and are only found in very obscure areas of a diet. And the lone remaining man out - Lactose (aka “milk sugars”) - will be covered in a forthcoming article based on Dairy.
Simple sugars, also known as Monosaccharides, comprise primarily of two types that you’ve likely heard of: Glucose and Fructose. The blood glucose that we have as a measurement of good blood health and of good insulin sensitivity is a measurement of the sugar Glucose. And the high fructose corn syrup that we find on labels such as sodas refers to the sugar Fructose.
The primary difference between these two resides in the process by which they’re metabolized. In other words, how our body processes them and then later utilizes them. And it’s through this filtration process where we begin to see how one type of sugar can wreak more havoc on our health than the other.
As alluded to above, Glucose is our blood sugar, and it serves as the same across all animal species. Glucose serves as the primary and most important source of energy as well, also across all species. Many are now familiar with the Ketogenic Diet. There, via consuming a predominantly fat-based diet, our bodies shift over to utilizing ketones as fuel. However, our default mode is glucose. When we consume carbohydrates, we intake this dietary glucose that keeps ourselves going, or we convert other carbohydrate substrates into glucose.
Given that glucose represents our blood sugar, it may seem intuitive that glucose metabolism occurs in the bloodstream. Virtually all cells in our body can use glucose for fuel, allowing for it to disseminate throughout the body while it’s being processed. While the liver processes some, it’s primarily utilized elsewhere. And the portion that the liver does process (generally 20% or less) is preferentially used to replenish glycogen in the liver before anything else.
[Glycogen, as a side note, is an energy source that is equivalent to fuel reserved for our highest gear. When we engage in a full sprint or an extraordinarily heavy lift, we’re tapping into our glycogen system. We also store glycogen in our muscles, which is utilized first during these bouts of intense activity (we touched on this in an article here.). But we expend liver glycogen slowly just by going about our day, so there’s generally some topping off needed there. During circumstances where we’re without glucose coming in the door, glycogen is broken down into glucose to be used as an energy source throughout the body. We can consider glycogen as a generator, assisting us when our power goes out, or when we need an additional surge that our everyday baseline electric panel can’t quite handle on it’s own.]
Glucose, however, raises our blood sugar levels more rapidly than any other type of sugar, igniting the engine of insulin production. We all know that high blood sugar levels are best to be avoided. And likewise, insulin, which increases as a result of a rise in blood sugars, is not the kind of guy we want hanging around for a while. This would seem to paint glucose in a most negative light in comparison with other sugars...right?
Enter Fructose. Whereas Glucose is capable of being metabolized throughout the entire body due to its usefulness to virtually all of our cells, Fructose must be metabolized in the liver. Our cells elsewhere have no use for it, and so it’s all funneled to one vital organ. In the liver, Fructose must be converted to Glucose in order to create usefulness for it elsewhere in the body. This process is time consuming. Glucose hits our bloodstream with little interruption, leading to its ability to raise our blood sugar levels quickly. While Fructose, through this filtration process, makes its way to our bloodstream more slowly and less entirely, leading to a comparatively lower spike in blood sugar and thereby less insulin. Shouldn’t this be a good thing?
The devil lies in the details of what’s left behind in the liver. Not all Fructose finds itself converted into Glucose for use as energy or glycogen replenishment. The Fructose that lags behind is stored as fat. It places a tremendous burden on the liver, in addition to manifesting itself in actual body fat accumulation. Risks of Obesity and Fatty Liver Disease are heightened in the presence of excess Fructose intake, with all things equal in comparison to Glucose, as are those of Type 2 Diabetes and Insulin Resistance.
Interesting tidbit: Fructose is processed in the liver, much like alcohol. There is some evidence to suggest that it has similarly addictive qualities via some interplay with the brain. Grehlin, our hunger hormone that we delved into last week (link here), is suppressed in the presence of Fructose, leaving us thinking that we’re not satiated when our bodies may want to suggest otherwise. This obviously leads to a compulsion to overeat.
And then there’s Sucrose. Sucrose is a hybrid sugar, consisting of one molecule of Glucose + one molecule of Fructose. Because Sucrose is a disaccharide, it must be broken down into its constituent parts before the body can use it. Our bodies manufacture an enzyme named sucrase to split this disaccharide back into two monosaccharides. They are then absorbed via their individual methods which have already been described. The presence of Glucose works against Fructose in this scenario, increasing the amount of Fructose that is absorbed while jointly increasing the production of Insulin via the blood sugar spike that the Glucose creates. The negative synergy here is that more Fructose is now being aggressively stored as fat.
High fructose corn syrup has (unfortunately) become the most abundant source of Sucrose in our diets. This should explain the rightful bad rap that it’s received, and is a surefire example of how a soda habit can lead to deleterious weight gain, among other ill health effects. It’s clear to almost everyone that consuming soda or other high fructose corn syrup laden products is likely unhealthy. But why would drinking a canned beverage on the regular assist in making us obese? This is the answer.
How to Know Which Type of Sugar You’re Consuming
One tool for testing sweetness levels is simply to use our sense of taste. As a general rule, Fructose is the sweetest tasting sugar. As you can probably guess, Sucrose follows behind, and Glucose falls in as the least of the three in terms of sweetness.
Fructose occurs naturally in most fruits, and also in vegetables. Hate to say it, but fruits can easily be overeaten. They taste amazing and contain a slew of nutritional benefits, but we should learn to eat the sweet ones in moderation. And with vegetables, we want to be cognizant of the same. Beets are referred to as “Nature’s Candy” for good reason. They taste amazing and they have a surefire place in a balanced diet (hence their inclusion on our menu), you just need to be sure not to overdo it. Honey and Maple syrup also fall into the Fructose category, as far as real foods are concerned.
The most valuable lesson to be gleaned with Fructose, however, is that virtually all added sugars contain an unwelcome amount. Sauces, dressings, etc. When sourcing or creating condiments, focus on there being as many whole foods as possible. On the flipside, avoid those that contain added sugar. And be wary of packaged foods that posture as real: canned fruits/vegetables, ketchups, jellies, etc. Chances are there is manipulation to the recipe that involves a dangerous culprit named sugar.
What may be surprising is that Sucrose is found naturally in many foods. However, it’s important to understand the context within which it’s found. Bananas, which are on the sugary side where fruits are concerned, contain Sucrose. They also contain heavy amounts of Potassium and Fiber. If you’re a follower of this newsletter then you know full well what a positive impact fiber can have on otherwise suspect food constituents (To learn more about Fiber if you missed that article, click here.). Bananas are a great food source. But like beets, they’re not something you’re wanting to consume in droves.
The Sucrose we must be most mindful of is granulated sugar. The fine, white substance that we use so often in baking and seasoning. It's refined mainly from sugar cane (and also sugar beets) and packs a devastating anti-nutritional punch.
Grains and Dairy tend to be leaders in predominantly Glucose-based sugar composition. Neither contain fructose. Only when tampered with, does Fructose come into the equation. Take whipped cream, for example. Though derived primarily from dairy, whipped cream will almost always see the inclusion of added sugar in its recipe. And in these cases, the ingredients label will simply read “Sugar”. Any time you see that, it’s an understanding that you’re receiving a dose of both Glucose and Fructose together, which we now know we should strive to avoid. It’s Glucose and Fructose combined that form what we all know as “table sugar”.
Pure Glucose is also found in some Nut Butters, and forms the minuscule sugar makeup in otherwise fatty foods such as Meat, Fish, Avocados, and Olive Oil.
EAT REAL FOOD
There are many primitive cultures with extraordinarily high carbohydrate intake yet very low incidents of Hyperinsulinemia, Type 2 Diabetes, and other conditions born largely of excess sugar consumption. The key in these cases is the abundance of real foods. Real foods wrapped in a fiber matrix have a protective barrier, preventing sugar from overwhelming us to its highest degree. The same can be said for the fat and protein macronutrients that also accompany most real foods. A diet rich in naturally occurring sugar is certainly dangerous, and the case for one consisting of predominantly beets and bananas was laid forth earlier. But by eliminating processed food, you’re really winning well in excess of half the battle. Once you’ve won on that front, allow your taste buds to be your guide. If it’s real and it’s sweet, then enjoy...just don’t get carried away.
Stay Real, and Sweet