Why the side effects of sugar are based on flawed research and how to make sugar work for you instead of against you

Sugar is the most evil substance in our diet of late, or so it’s portrayed by the media and a ton of “expects”.

The only positive thing about it is that it’s sweet right?
The rest is just side effects.

Well, that’s because people don’t read all the research.
How can you conclude that something like sugar is bad when it isn’t balanced in the diet with “co-factors”.
Without enough co-factors sugar can negatively effect you yes. But without enough co-factors/micronutrients in the diet, you’ll have a lot more to worry about than just sugar.

So is sugar the bad guy or rather a lack of micros?

In this article I’ll be discussing and debunking the top 6 “side effects” that sugar has.

Side effect #1: Sugar negatively modulates the gut bacteria.

All Disease Begins in The Gut.” – Hippocrates.

Feeding animals a high fructose diet is shown to create an obesity phenotype characterized by a markedly increased ratio of Firmicutes/Bacteroides (certain gut bacteria strains) in the gut.

This leads to an increase in endotoxins, gut permeability, liver inflammation, damage and just overall chaos in the gut.
This is a good reason to cut out sugar right?

No, actually not. Animal models that portray this are given a very high fructose diet of about 30% of their calories (which is a lot and unnatural) and we all know that laboratory made food for animals suck. The reason why most of these side effects happen is largely due to a copper deficiency. 

Firstly, copper is anti-microbial and secondly, one of the copper containing enzymes, diamine oxidase, is found in high concentrations in intestinal mucosa. Its circulating enzyme activity serves as a marker of mucosal maturation and integrity, as does the level of copper. Thus, decreased copper levels may exacerbate dietary fructose-induced gut microbiota dysbiosis and/or gut barrier dysfunction (R).

Thirdly, sugar is very rapidly absorbed because it doesn’t require digestion. The combination of glucose and fructose (which is sugar), synergistically increases the absorption of each other. That is why athletes use sugar because it absorbs and replenishes glycogen stores so rapidly.
So the chance of sugar reaching the colon where the gut bacteria actually is, is very very slim.

However, if you get indigestive issues from a fruit, chances are that it’s not the fructose, but rather an adverse reaction to the fiber in the fruit. Or if you get a reaction to fruit juice, it’s most like an inferior quality product. There is much to be said about mass produced products such as most fruit juices.

Lastly, there are enzymes in the gut which convert fructose into glucose and lessen the chance of the fructose reaching the colon even more.

Summary of this side effect:
Chances of fructose reaching the colon is minuscule, if not impossible, unless someone has some serious digestive issues. Secondly, fructose might cause a concern if copper is deficient. Don’t frame fructose as the bad guy if your diet isn’t good and lacks copper.

Side effect #2: Sugar promotes a leaky gut

As mentioned in the point above, diamine oxidase, is found in high concentrations in intestinal mucosa and its circulating enzyme activity serves as a marker of mucosal maturation and integrity, as does the level of copper. 

Furthermore, the expression of the tight junction proteins, claudin-1 and occludin, are significantly down regulated in the ileum of rats fed a marginal copper deficient diet (R).
This effect was synergistically or additionally enhanced by high fructose feeding.

Additionally, hypoxia induced factor -1 (HIF-1) plays a central role in the protection of gut barrier function in multiple ways and it’s known that copper is required for the activation of HIF-1.

Again, is fructose the bad guy here or is it a lack of micronutrients such as copper?

Side effect #3: Sugar causes fatty liver and promotes obesity

Fatty liver and obesity are probably the most well known side effects or causes of a high sugar/fructose intake. And there are tons of studies to prove it, so we just read the abstract and maybe the discussion and be done with it, right?

Well, fatty liver is basically the accumulation of fat in the liver, however, this can happen due to low protein, low choline and/or low copper intake (R).

Even a marginal copper deficient diet can lead to a upregulation of hepatic fatty acid synthase (FAS) protein expression and is exponentially worsened by high fructose consumption (R, R). 

Using an iron chelator can help to mitigate the damages.
When copper is deficient, iron starts to accumulate, especially in the liver. NAFLD patients, with low copper levels, were shown to have hepatic iron overload (R). Iron is a potent inducer of FAS and de novo lipogenesis (DNL). This is because copper is needed for the transport of iron. Cellular iron export requires members of a family of copper-containing ferroxidases, including ceruloplasmin and hephaestin (which oxidize iron from the ferrous to ferric forms).

Hepatic iron overload, due to too high intake (think fortified food) or due to inadequate copper intake, may contribute to hypertriglyceridemia and hypercholesterolemia (R).

Data show that levels of dietary iron, not the type of dietary fat, are potential inducers of hypertriglyceridemia. Data also show that the combination of high iron intake and dietary copper deficiency is responsible for elevating blood cholesterol (R). Lowering iron and upping copper lowers triglycerides and cholesterol.

Again, is fructose the bad guy? It could be if copper is deficient. Fructose could cause or contribute to fatty liver, hypertriglyceridemia and hypercholesterolemia if copper is low and iron accumulates.

As a side note: even if fat did accumulate due to the fructose converting to fat, the saturated fat is not harmful and does not damage the liver. It’s the unsaturated, and not saturated, fat that increases liver enzymes, such as ALT, and promotes hepatic steatosis and inflammation (R).

Side effect #4: Sugar is inflammatory

This “fact” is also heavily linked to the fructose-copper interaction.

Superoxide dismutase (SOD), which reduces free radicals (reactive oxygen species (ROS)) such as superoxide to hydrogen peroxide, is copper dependent. When ROS production goes too high it causes inflammation, DNA damage, mitochondrial damage and this lowers energy production, DNA formation, hormone production, etc.

Additionally, excess iron, due to low copper levels, is also highly inflammatory. Iron reacts with oxygen, creates ROS and thus results in copious amounts of inflammation.

Side effect #5: Sugar is a metabolic toxin

So sugar is shown to increases D-lactate, L-lactate, increases uric acid, promotes insulin resistance, etc.

Let’s start with D-lactate. D-lactate is the more harmful compared to L-lactate. D-lactate is produced from methylglyoxal, which is produced from glyceraldehyde 3-phosphate; an enzyme in glycolysis. Fructose can potentially increase D-lactate because it rapidly enters the cell, faster than glucose, and theoretically runs faster through glycolysis than glucose, thus creating more methylglyoxal.

True enough, eliminating fructose from the diet in obese children and replacing it with glucose resulted in a drop in D-lactate, L-lactate, Hb1Ac, liver fat, insulin, triglycerides, cholesterol, DNL and glucose (R).

So does this show us that sugar is bad or that these kids were eating a terrible diet in general which is deficient in a lot of micronutrients? As discussed above, a deficiency in copper and an accumulation of iron leads to hypertriglyceridemia and hypercholesterolemia.

Methylglyoxal is elevated during a deficiency in vitamin B1 (R), glutathione (R), zinc, vitamin E (R), vitamin C (R) and can be lowered by many beneficial compounds found in fruits, veggies and spices (R). Eating a diet rich in fresh fruits, which supplies a lot of fructose, lowers blood sugar and Hb1Ac over time (methylglyoxal increases Hb1Ac). As a side note, polyunsaturated fat also increases methylglyoxal.

Onto L-lactate… A deficiency in vitamin B1 (R, R), biotin (R), copper (R, R) and magnesium (R) is shown to lead to an increase in L-lactate.

Lastly, fructose increases uric acid levels. Uric acid is produced through purine breakdown, or because of rapid energy breakdown (which is due to insufficient recycling or production); AMP is not reconverted to ATP, so it gets broken down.

There is a positive association between ferritin (iron storage form due to excess iron intake or low copper levels) and uric acid (R). In the presence of very low iron levels, uric acid doesn’t promote oxidative stress or cause gout attacks and inflammation (R).

Furthermore, low vitamin D, dietary calcium intake and elevated parathyroid hormone (PTH) levels increase uric acid retention and accumulation.

Caffeine and creatine can help to recycle AMP to create ATP. Fructose actually lowers phosphorus (phosphorus increases parathyroid hormone) and increases thyroid and ATP production.

Side effect #6: Sugar increases cortisol

The last, but not least, side effect of sugar is that it’s thought to increase cortisol.

However, sugar actually decreases 11β-HSD1 mRNA (R), the enzyme that activates cortisol and sugar also increases the NAD:NADH ratio (R), which is needed to deactivate cortisol; both of which will lead to less cortisol production, keeping stress under control. This study also shows that sugar was just as effective as bananas at lowering cortisol (R).

In short, sugar doesn’t increase cortisol, but can actually help make you more stress resilient.


As you can see, sugar is really not as bad as it’s made out to be. Now I’m not advocating to go and stuff your face with sugar and even less so with sweets and cake. But I am trying to make you more conscious of how crucially important a micronutrient rich diet is.

Whole fruits are very healthy and can improve all health markers. Fruit juice is also a great option if you can find a good quality source, but then just make sure your micros are on point before going heavy on the juice.

Lastly, sugar can be used, but don’t go bonkers with it.
If you want to consume a lot of sugar, then you have to make absolutely sure that your diet is micronutrient rich. Don’t just think your diet is rich because you’re eating healthy.
I would highly advise logging your foods into cronometer to get a better idea of what is going on.

As always, thanks so much for reading my article.
If you found it helpful and insightful please like and share so others can also benefit from this information and feel free to leave a comment down below if you have any questions for me.

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3 Replies to “Why the side effects of sugar are based on flawed research and how to make sugar work for you instead of against you”

  1. Hans, your articles are amazing and I can’t wait to dive into the next one. I appreciate it very much. Thank you.

  2. Your articles are amazing and I can’t wait to dive into the next one. I appreciate it very much. Thank you.

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