[For background context: I am currently still interning with EChO-Eradicate Childhood Obesity Foundation, and so I spend a lot of time thinking about and researching sugars].
Ask anyone- I love sweets. I’m pretty indiscriminate about what types (though I tend to prefer baked goods to pure candy). At either rate, one thing I have worried about over the years (and not necessarily due to any scientific reasoning) was that my previously very high sugar consumption as a child/teen had somehow contributed to my global body eczema flares now (despite not eating as much sugar these days). This has led me to be particularly interested in researching more about sugar, and it’s potential links with eczema.
So let’s get into the nitty-gritty about sugar. The term sugar, much like the term bacteria, often gets a bad rep. Sugar is a type of carbohydrate (the others being polysaccharides and oligosaccharides), that is best defined as either monosaccharides or disaccharides (‘saccharide’ means ‘sugar’). Monosaccharides include simple sugars like glucose (dextrose), fructose (levulose), and galactose. Disaccharides includes sucrose (or what we know as table sugar) which is made of glucose and fructose, maltose (a sugar from grains made of 2 glucose molecules), and lactose (a sugar from milk and made of glucose and galactose). You may have heard fructose (the sugar that makes fruit sweet) getting a bad rap, and that’s because the way the brain processes fructose versus glucose differs. Studies done on rats show that when glucose was consumed, a “satiety” response eventually kicks in because glucose triggers the hormone insulin to be released, but when fructose was consumed, there wasn’t enough of an insulin response to cause the same feeling of satiation. What does this mean globally? Well, consuming fructose sugars may take longer for you to feel full or done eating, and so as a result you are more likely to eat/consume more of whatever food/drink it’s in before you feel done. But why are fruits okay to consume (in moderation)? Because they are packaged naturally with fiber and other nutrients and are not just added fructose (think like how many products, like sodas, often have/had high fructose corn syrup, or extra fructose in them but no fiber or other healthier aspects to balance them out).
It is also worth noting about polyols. Some sources consider this to be a type of sugar (such as the World Sugar Research Organization), while others say it is not a sugar, but it is a carbohydrate (Polyols Organization). Polyols can sometimes be called ‘sugar alcohols’ because their structure looks somewhat like a sugar molecule and somewhat like an alcohol molecule. Polyols include: erythritol, hydrogenated starch, hydrolysates, isomalt, lactitol, maltitol, mannitol, sorbitol, and xylitol. They are seen as a new alternative to sugar because they don’t spike blood glucose levels, and they generally have fewer calories per gram. Currently the warning with them is that they may make still be addictive and cause people to consume larger quantities of foods that contain them and/or start to dislike products that don’t have them. The adverse side effect listed by the FDA of excess consumption of polyols is usually related to digestive issues (gas, bloating, diarrhea, etc). Anyway…
The function of sugar in our bodies is to produce energy. When we eat carbohydrates our body breaks it down into glucose and uses those molecules to do important functions like activating our muscles. However, the rates at which sugar affects our blood sugar levels varies. Simple carbohydrates (like sucrose, or table sugar) increases our blood glucose levels quickly, while complex carbs (whole grains, beans, etc) affect blood glucose levels more slowly. In this case we have another example of how slow and steady wins the health race- fast blood glucose level spikes means insulin is released quickly (insulin is used to help cells take in glucose), as a result, you’ll want more sugar again more quickly after eating a blood glucose spiking diet and also, diseases like diabetes and heart disease are related to blood glucose level spikes.
So why are some sugars considered worse than others? The term “added sugars” is a more recent addition to our nutrition world vocabulary and is used to talk about when products include sugars that are not naturally in food (such as when we add a table sugar to the cake batter we are making for a birthday). For example as mentioned before, fruits contain the sugar fructose, but it is considered a natural sugar because one, it is naturally created by the fruit, and two, because it is packaged in the fruit with a balance of fiber and other micronutrients. The problem is that a lot of our processed foods have more added sugar than we think, and dietary guidelines about how much sugar we should maximally eat in a day are being exceeded (according to the American Heart Association, women should eat no more than a total of 6 teaspoons of added sugar a day, and men no more than 9 teaspoons). So if you had a seasonal tall (aka a small) Starbucks Pumpkin Spice Latte this fall with 2% milk and no whipped cream, you consumed about 37 grams of added sugar, or 7.4 teaspoons, exceeding the max a women should have in a day and getting close to the men’s max as well, with one beverage.
But how does sugar impact skin? It affects it in a few ways: by causing inflammation, by aiding candida infections (people with eczema often have a higher risk of candida infections), via glycation, and by messing up our sleep.
When it comes to inflammation, the issue tends to be that sugar (fructose in particular) as its metabolized by the liver can cause free radicals to be made, which are known to cause inflammation. Inflammation results in cell damage, and with a condition such as eczema where your body is already in hyperdrive of attacking its own cells, increasing cell damage is the last thing you want. Interestingly enough, studies on rats have shown that strength training helps to control inflammation even with a high-fructose diet, but I’ll talk about exercise and activity in another post.
Candida albicans is a type of yeast (or fungus) that many healthy people carry orally, and can be non-pathogenic if there is not an overgrowth of it. When there is too much (or any other type of Candida yeast), the condition is called candidiasis. Though there are many reasons for why we’ve seen an increase in candida infections, some of the major culprits are increases in antibiotic use, use of topical or oral corticosteroids (or other local immune suppressors), as well as refined sugars changing our pH, and allowing for easier growth of this yeast. The problem with candidiasis is it can lead to bloodstream infections, and it can cause increased production of acetaldehyde, a chemical that breaks down DNA and impairs cellular repairs. Now it stands to say again that sugar isn’t the only cause for increased risk of candidiasis, but in tandem with taking corticosteroids and antibiotics, it doesn’t help.
Glycation (or more technically described as advanced glycation end products, or AGEs), are products created by a reaction called the Maillard/browning reaction- a reaction that occurs in normal metabolism, but if too many AGEs are made that’s when it becomes a problem because they can increase inflammation and oxidation stress in the body. Usually, AGEs are released by cooking animal-based foods at high heats, more so than by cooking fruits, veggies, whole grains, etc (unless the fruits/veggies/whole grains are made with added fats, in which case the dietary AGEs are also drastically increased). Increased AGEs can also impact collagen and elastin production (due to the oxidation effects), which would impair wound healing. So how does this relate to sugar? Well sugars such as fructose, in combination with some animal protein components heated together increases the dietary AGE production. A low dietary AGE intake, much like a low sugar diet, can help fix insulin sensitivity and improve wound healing (especially with the subsequent decrease of inflammation that occurs). But if your snack/sweet of choice are baked goods made with animal/protein-rich products and includes fructose, chances are you are upping your AGEs, therefore decreasing wound healing, increasing inflammation, and impairing insulin sensitivity.
And lastly, sleep. Simply put, if you eat a lot of sugar, your body has to spend more time trying to convert it into energy and/or store it as fat, and so if you are eating enough to have the ‘food coma’ effect at night, chances are you are slowing your body’s recuperating abilities as it spends the time trying to handle sugar, instead of focusing on general repairs (such as healing eczema rashes and cuts). When we ultimately hit the sugar crash point, our bodies produce cortisol, which results in a higher heart rate, and subsequently less good sleep. Ironically it’s a cyclical pattern. The more you lose good sleep, the more likely you may be to crave sweets!
So the takeaway? Sugar (and specifically added sugars) definitely don’t help eczema, especially when eaten in excess.
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