Last time I checked, 1 comes before 2. So, if you haven’t read part 1 of this series yet, you should probably go do that first.
If there has been one aspect of food that has been demonized the most, I would certainly throw sugar into the ring.
Just as I attempted to dismantle the notion that carbohydrates are inherently evil, I plan on doing the same with sugar.
Now, I am certainly not going to suggest that all calories are equal here. I did a separate piece on why I do not agree with that statement. Of course, hormones, digestion, and other factors come into play. But, as I demonstrated in the first part of this series, I do not think we can simply point our finger at insulin, or high energy density fats and say “yep you are the sole reason for weight gain.” That is asinine.
Yet, for some reason, people have the notion that if even 1g of carbs or sugar goes down their gullet, they will most certainly pack on the pounds. And it is no fault to you. Clever marketing schemes, people pushing their diet dogma, and of course just pure ignorance to the science has led this to be a prevailing thought.
And it doesn’t seem like it matters who you ask…everyone seems to agree that sugar should be avoided like the plague. My question is: why do we have this assumption, and of course, does the literature back this claim up?
To give you enough background info I am going to need to wave my magic biochemistry wand.
Let us take table sugar as our example. Table sugar (sucrose) is what we in the biz call a disaccharide. Di, meaning 2, and saccharide, meaning sugar. So, sucrose is simply two sugar molecules linked together. Whereas, sucrose’s more popular cousin, glucose, is a monosaccharide (meaning it is a single sugar monomer…the simplest form and ready to be used as fuel!). So, when we ingest sucrose, our end goal is to break that disaccharide into a monosaccharide so we can use it to fuel our body!
As this is what I am currently studying at NIH, I will be a bit more specific. Sucrose is composed of 1 molecule of glucose bonded to 1 molecule of fructose via an α-1,β-2-glycosidic linkage. I won’t go into the importance of this bond as that would go too far into the weeds, but if anyone wants more info, just reach out.
Thus, we ingest sugar, and eventually it will make its way to the small intestine where the enzyme sucrase will cleave it into individual molecules of fructose and glucose, so we can use them for energy (BeMiller, 2018).
The same rings true for complex carbs. For instance, Amylose, a polysaccharide (multiple monosaccharides linked together…very long chain) found in grains, legumes, potatoes, etc… is broken down into maltose (two glucose molecules linked together) and single glucose molecules by salivary and pancreatic amylase enzymes. Maltose is then cleaved into individual glucose molecules via the enzyme maltase. So at the end of the day, just like sucrose being broken down into usable fuels like fructose and glucose via sucrase, complex carbs are broken down in a similar fashion (albeit complex carbs take longer to break down and absorb….but that is a different argument).
OK, hopefully that taught you something interesting about carbohydrate biochemistry, and now you have something cool to tell Grandma about. But now for the good stuff. Why is sugar seen as being so bad for us? What gives?
Well, we do know increased sugar consumption is associated with higher rates of obesity, heart disease, and cancer (Howell & Wilson, 1969; Stanhope, 2016; Sulaiman et al., 2014).
Oh well I guess I was wrong. Seems like an open and shut case…article over.
Yeah see, that’s where we go wrong. We see an epidemiological study like these 3 that point to increased sugar consumption at the root of all our problems and just take their word for it, without digging deeper. Studies like these are what have those clown college trainers at the gym telling you to reduce your sugar consumption or eliminate it from your diet. Often this leads to insatiable cravings and binging…not good.
This doesn’t just apply to science, but if you just take someone else’s word on something and can’t draw your own conclusions, then there are some major problems that need to be fixed. With that in mind, let us dig a bit deeper.
The question that really needs to be asked is: is it the sugar that is really the problem…or all the empty calories sugar contains (by empty calories I mean calories that essentially give you no satiety or micronutrients).
For instance, let’s look at everyone’s favorite beverage…soda!
1 bottle of Coca Cola (20 fl Oz) contains 65g of sugar (for a total of 240 cals per serving; Coca-Cola, 2021). For the sake of the argument, let’s say someone drinks one of these per day, that’s an extra 240 cals per day when compared to drinking a zero-calorie liquid. Those 240 calories could be the difference between you maintaining your weight and gaining weight. And to make matters worse, lets add in that cup of OJ you had for breakfast (per 8 fl oz of Tropicana; 110 cals, 22g sugar) and that chocolate bar you had after dinner (per 1 Snickers Bar/1.9 oz; 250 cals, 27g sugar). Wow now we have a real problem on our hand. This is an extra 114 g of sugar and 600 cals per day!
Products like Coca-Cola, OJ, and chocolate bars are manufactured to be hyper-palatable, and the fact that they offer very little satiety leads to overconsumption and inevitable weight gain.
However, the common myth that is perpetuated today is that somehow the consumption of sugar is a more potent lipogenic agent (increased fatty acid storage and fat storage) than other carbohydrates. Is there any truth to this claim?
Correlation does not Equal Causation:
As stated above, the epidemiological data does link sugar and obesity, but is their actual causal data out there to show that sugar consumption is driving fat gain?
A study of 398 obese adults placed on either a low sugar diet, a high sugar diet, or a control diet aimed to investigate the impact of sugar intake on body composition. At the end of this six-month trial, there was no difference in body weight, body fat, and blood lipids between the low sugar and high sugar groups. Importantly, protein, calories, and fiber were equal in the two experimental diets, thus truly getting at the impact of low vs high sugar consumption itself (Saris et al., 2000).
Ok, now I’ve got a good one for you. I am sure you have been told that you most certainly can’t eat sugar while trying to lose weight! Well, that is exactly what West & De Looy, (2001) set out to investigate.
In this study, the researchers recruited 68 overweight subjects and placed them in a 600 kcal/day deficit to elicit weight loss. Subjects were randomly placed in a low sugar diet group (5% sucrose, 33% fat) or a high sugar diet group (10% sucrose, 33% fat) for 8 weeks.
At the end of the 8 weeks there was no significant difference in weight loss or BMI between the two groups (actually the high sugar group lost almost 2 lbs more than the low sugar group). And if this difference of 5% in sucrose between the two diets doesn’t quite do it for you, get this. One study gave obese women a diet where sucrose composed 4% of total daily energy (11g sugar) and the other group of obese women a diet where sucrose composed 43% of total daily energy intake (118g sugar). Six weeks later and despite this mammoth difference in sugar intake, there was no significant difference in weight loss, metabolic rate, plasma lipids, or emotional affect between the groups (Surwit et al., 1997).
Along similar lines, Drummond et al., (2004) initiated a 12-week dietary intervention placing 76 middle-aged men in caloric restriction on a higher sugar diet. Prior to the intervention, on average the men were consuming their energy from 38.1% fat, 44.4% carbs, and 17.3% protein. The subjects were then given the dietary advice and placed on the energy restricted diet, which at the end of the 12 weeks was composed of 26.2% fat, 54.4% carbs, and 20.6% protein. Despite increasing the sugar consumption in their diet, these men on average saw significant reductions in body weight (5.2%), body fat (11.2%) and waist:hip ratio (3%)
And I know some of you are probably raising your eyebrows at this point. These studies do in fact demonstrate that when we control for calories, the sugar content of the diet does not matter. A calorie deficit, even with sugar will lead to weight loss.
Yet, there is a problem: these are free-living situations, so who knows what was really going on behind the scenes. Well I got you, don’t worry.
22 Obese subjects were placed into either the low glycemic, high glycemic, or high fat group in a University of Minnesota Study. Regardless of the diet group, all subjects were placed on a calorie deficit of 750 calories and then for 12 weeks the corresponding meals were prepared and consumed in the controlled setting of the University of Minnesota Metabolic Unit. Following the 12 weeks, subjects were instructed to maintain the same dietary approach and continue their own for 24 weeks. At the end of these combined 36 weeks each group lost weight and had improved insulin sensitivity (no significant difference between groups) despite eating different amounts of sugars. Thus, the researchers concluded, “lowering the glycemic load and glycemic index of weight reduction diets does not provide any added benefit to energy restriction in promoting weight loss in obese subjects.” (Raatz et al., 2005).
So, what do we take from these data? Well it is the caloric load and not the sugar itself that dictates weight gain or loss. Hence, if we are cognizant about our caloric load, sugar seems to not make an impact on weight loss or weight gain.
Ok, if none of this has quite done it for you, I’ve got one more thing to throw at you. While it seems that one can eat absurd amounts of sugar and still lose weight if they are in a calorie deficit, surely higher sugar consumption causes other health problems, right?
Well, the data seems to suggest that once again, when we equate calories, protein, total carbs, and fiber, and then incorporate moderate amounts of sugar into the diet, there is no significant change in blood pressure, thyroid hormone, insulin, cholesterol, blood lipids, blood glucose, or inflammation (Raatz et al., 2005; Saris et al., 2000; Surwit et al., 1997; West & De Looy, 2001). Even high-fructose corn-syrup, the red-headed stepchild of nutrition, has been shown not to cause weight gain or alter blood lipid values when calories are held in check (Lowndes et al., 2012).
So, am I telling you to go out and eat sugar by the spoonful? Absolutely not! However, what I am trying to show you is that if you are a metabolically healthy individual with no underlying metabolic dysfunction, sugar can absolutely have a place in your diet as long as you are cognizant of your daily caloric load.
Now of course, there are disadvantages to adding sugar into your diet. Primarily that it will not fill you up at all and is very easy to overeat. But, if a piece of fruit or a tablespoon of honey would make you happy, then go for it. If you budget this sugar into your daily calorie balance, it can be highly beneficial. For instance, it can curb cravings, serve as pre workout fuel, post workout recovery, and positively influence your emotions.
So, when the dust has finally settled, I hope these two articles have opened your eyes a bit. It is most certainly not our fault for being so blind to the truth. In fact, prior to my arrival at NIH, I too thought carbs and sugar should be avoided at all cost. Yet, I learned quickly, that if you do a bit of digging, you can find a whole lot of truths out there…and most of them are quite contrary to what we typically believe. It is time for the veil to be lifted.
BeMiller, J. N. (2018). Carbohydrate chemistry for food scientists. In Carbohydrate Chemistry for Food Scientists (pp. 1–427). https://doi.org/10.1016/C2016-0-01960-5
Coca-Cola. (2021). Coca-Cola® Original | Coca-Cola®. https://us.coca-cola.com/products/coca-cola/original/
Drummond, S., Dixon, K., Griffin, J., & de Looy, A. (2004). Weight loss on an energy-restricted, low-fat, sugar-containing diet in overweight sedentary men. In International Journal of Food Sciences and Nutrition (Vol. 55, Issue 4, pp. 279–290). https://doi.org/10.1080/09637480412331290495
Howell, R. W., & Wilson, D. G. (1969). Sugar and Ischaemic Heart Disease. In British Medical Journal (Vol. 4, Issue 5682, pp. 559–560). https://doi.org/10.1136/bmj.4.5682.559-c
Lowndes, J., Kawiecki, D., Pardo, S., Nguyen, V., Melanson, K. J., Yu, Z., & Rippe, J. M. (2012). The effects of four hypocaloric diets containing different levels of sucrose or high fructose corn syrup on weight loss and related parameters. In Nutrition Journal (Vol. 11, Issue 1). https://doi.org/10.1186/1475-2891-11-55
Raatz, S. K., Torkelson, C. J., Redmon, J. B., Reck, K. P., Kwong, C. A., Swanson, J. E., Liu, C., Thomas, W., & Bantle, J. P. (2005). Reduced glycemic index and glycemic load diets do not increase the effects of energy restriction on weight loss and insulin sensitivity in obese men and women. In Journal of Nutrition (Vol. 135, Issue 10, pp. 2387–2391). https://doi.org/10.1093/jn/135.10.2387
Saris, W. H. M., Astrup, A., Prentice, A. M., Zunft, H. J. F., Formiguera, X., Verboeket-Van De Venne, W. P. H. G., Raben, A., Poppitt, S. D., Seppelt, B., Johnston, S., Vasilaras, T. H., & Keogh, G. F. (2000). Randomized controlled trial of changes in dietary carbohydrate/fat ratio and simple vs complex carbohydrates on body weight and blood lipids: The CARMEN study. International Journal of Obesity, 24(10), 1310–1318. https://doi.org/10.1038/sj.ijo.0801451
Stanhope, K. L. (2016). Sugar consumption, metabolic disease and obesity: The state of the controversy. In Critical Reviews in Clinical Laboratory Sciences (Vol. 53, Issue 1, pp. 52–67). https://doi.org/10.3109/10408363.2015.1084990
Sulaiman, S., Shahril, M. R., Wafa, S. W., Shaharudin, S. H., & Hussin, S. N. A. S. (2014). Dietary carbohydrate, fiber and sugar and risk of breast cancer according to menopausal status in Malaysia. In Asian Pacific Journal of Cancer Prevention (Vol. 15, Issue 14, pp. 5959–5964). https://doi.org/10.7314/APJCP.2014.15.14.5959
Surwit, R. S., Feinglos, M. N., McCaskill, C. C., Clay, S. L., Babyak, M. A., Brownlow, B. S., Plaisted, C. S., & Lin, P. H. (1997). Metabolic and behavioral effects of a high-sucrose diet during weight loss. In American Journal of Clinical Nutrition (Vol. 65, Issue 4, pp. 908–915). https://doi.org/10.1093/ajcn/65.4.908
West, J. A., & De Looy, A. E. (2001). Weight loss in overweight subjects following low-sucrose or sucrose-containing diets. In International Journal of Obesity (Vol. 25, Issue 8, pp. 1122–1128). https://doi.org/10.1038/sj.ijo.0801652