Nutrition
Zeroing in on Sugar Free: Diet Hack or Trap?
Nov
In today’s diet culture, dieting for fat loss has become somewhat synonymous with the use of terms like “sugar-free” and “calorie free.” I’m referring to the many protein bars, diet drinks & low-carb treats that stock the shelves of local supermarkets, promising the sweetness of the OG’s without the added calories. But “sugar-free” doesn’t always mean “calorie-free,” and these foods can be abused, bank hidden calories and cause digestive distress. This article digests some of the common food additives you see on the back of nutritional labels like artificial sweeteners, polyols, synthetic fibres, and bulking agents as well as their pros and cons for bodybuilders, especially those in a contest preparation.
Polyols (Sugar Alcohols)
Polyols like sorbitol, xylitol, maltitol, and erythritol are sugar alcohols used in sugar-free sweets, syrups, and protein bars. They’re lower in calories than sugar (typically 1.6-3 kcal/g), but not zero. Erythritol is an exception, providing ~0 kcal as it’s mostly excreted unchanged (Livesey, 2003).
The trouble? Labels often downplay these calories. For example, a syrup with sorbitol may claim “<1g carbs” but still deliver 18 kcal per serving which equates to more than 4g of untracked energy (Fernstrom, 2018). Think HaloTop Ice cream Queen’s Sugar Free Maple Syrup. For macro-tracking bodybuilders, these are hidden calories in disguise.
Polyols have a low glycemic impact, making them appealing for carb-sensitive dieters (Magnuson et al., 2016). Some, like xylitol and isomalt, even support beneficial gut bacteria (Grabitske & Slavin, 2009). But overdoing it can backfire (literally & figuratively) e.g. 20–30g in one sitting often leads to bloating, cramps, or diarrhea (Roberfroid, 2008). Erythritol is better tolerated, but even it can cause discomfort in large doses.
Polyols offer sweetness with fewer calories with stable blood sugar levels, but they aren’t “free” and can wreak havoc on your digestion if abused.
Aspartame (and Phenylalanine)
Aspartame is a low-calorie sweetener used in diet sodas (e.g. Coke No Sugar), protein puddings, and tabletop packets. It’s ~200x sweeter than sugar and contains phenylalanine, which is dangerous only to people who cannot properly digest phenylalanine (phenylketonuria or PKU. For everyone else, it’s broken down like any other amino acid (EFSA, 2013).
Decades of research have shown that aspartame doesn’t increase appetite or promote fat gain. In fact it may help reduce calorie intake when replacing sugar (Rogers et al., 2016). A 2014 RCT even found more weight loss in a diet soda group (aspartame users) compared to a water-only group during a structured diet (Peters et al., 2014).
Despite health scares, major regulatory bodies, including the FDA and EFSA, continue to deem aspartame safe within set intake limits (EFSA, 2013). In 2023, the WHO’s IARC classified aspartame as “possibly carcinogenic” and on par with things like aloe vera and pickled veggies however the basis of these claims were upon limited evidence. But their food safety arm (JECFA) reaffirmed the acceptable daily intake, citing no credible human risk (WHO, 2023).
Overall aspartame seems beneficial for calorie control and is safe for most. However you should monitor intake based on personal sensitivity and avoid if you have PKU.
Sucralose
Sucralose (aka Splenda) is another ultra-sweet, zero-calorie sweetener popular in protein powders and baking mixes due to its heat stability. It’s non-caloric because the body doesn’t metabolise it (Magnuson et al., 2017).
Sucralose has no significant effect on blood glucose or insulin when consumed alone. However, a few studies suggest that sucralose combined with carbs might affect insulin sensitivity (Romo-Romo et al., 2018). There’s also emerging research and a mixed consensus on its potential to negatively impact the gut microbiota. Some studies show no significant microbiome disruption, while others suggest possible changes in glucose metabolism (Suez et al., 2022).
In 2023, concerns were raised with sucralose-6-acetate (a possible byproduct), which showed genotoxicity in vitro (Schiffman & Nill, 2023). While not clear cut, these findings spark the need for more research in this area, particularly for those that consume high dosages over long periods.
Sucralose is effective and safe at normal intakes but may carry small, long-term uncertainties. Moderation is wise.
Synthetic Fibers (e.g. Polydextrose and Inulin)
Polydextrose and inulin are common “functional fibers” added to protein bars, low-carb snacks, and “high fibre” sweets to assist with adding bulk to a product and reduce it’s overall calories. Polydextrose is synthesised from glucose and has ~1 kcal/g where as inulin is a prebiotic fiber extracted from chicory with ~1.5–2 kcal/g (Roberfroid, 2008).
Both increase satiety, feed beneficial gut bacteria, and help meet fibre goals when veggies are low. Studies have shown polydextrose reduces hunger and delays gastric emptying (Hull et al., 2012), and inulin increases Bifidobacterium counts and may help with modest weight loss (Slavin, 2013).
However there is a silver lining. High doses can cause gas, bloating, and loose stools especially for inulin. Even 5-10g per serving is too much is too much for some individuals & symptoms severity may vary. Fibre “overdosing” via bars and supplements is a common cause of bloating in a diet phase.
These fibres can boost fullness but abuse can lead to some very uncomfortable GI distress. Ensure you monitor your own gut comfort if you plan on consuming products containing these types of fibres as well as ensure you track the properly towards your total calories.
Bulking Agents (e.g. Xanthan Gum)
Xanthan gum is a zero-calorie thickener used to bulk up protein shakes, low-calorie ice creams, and sauces. A pinch can turn a watery shake into “protein fluff,” giving the illusion of volume and fullness. Think your evening Ninja Creami or low calorie protein ice cream.
It’s technically a soluble fibre and contributes around ~2 kcal/g to your total calories. Research suggests viscous fibres like xanthan gum can increase satiety and slow gastric emptying (Edwards et al., 1987).
At smaller doses (under 5g/day) it seems to be commonly tolerated, however at very high levels (15+ g/day), it can cause gas, bloating and loose stools.
Despite it seeming like an alluring diet hack to stay full on fewer calories; just ensure don’t overdo it or you’ll turn your pudding into paste.
Dieting with Hyper-Palatable Foods
While sugar-free additives are often used to make dieting more enjoyable, it’s essential to consider the concept of hyper-palatable foods. These are foods engineered with combinations of fat, sugar, sodium, and carbohydrates that make them exceptionally rewarding and difficult to resist. Despite sugar free alternatives being designed to reduce the calories of foods, often the products they’re used in are hyper-palatable in nature.
A study by Fazzino et al. (2023) found that hyper-palatable foods independently contribute to increased calorie intake across various dietary patterns, regardless of energy density or eating rate. This suggests that even when consuming foods labeled as “diet-friendly,” their hyper-palatable nature can lead to overeating.
For bodybuilders and individuals aiming for weight loss, this presents a paradox. While sugar-free additives can help reduce calorie intake, their use in creating hyper-palatable foods might inadvertently stimulate appetite and cravings, making calorie control more challenging.
Incorporating sugar-free additives should be done with mindfulness. Relying heavily on hyper-palatable, diet-friendly foods can undermine dieting efforts by promoting overeating. Emphasising whole, less-processed and nutrient dense foods may aid in better appetite regulation and adherence to dietary goals.
The Final Scoop
When used smartly, sugar-free additives can assist fat loss through improved enjoyment & overall dietary adherence. They may help navigate cravings and avoid blowing the calorie budget for bodybuilders on strict contest preparation diets, however like anything; there are pros and cons to every strategy.
Mistracking calories (especially from polyols or fibre), over-relying on processed “sugar-free” items at the expense of nutrient dense whole foods, and ignoring GI side effects are all common caveats to using these products. The science shows these additives are generally safe and effective but moderation is key.
Ultimately these products should be used as a tool in the toolbox to assist in managing low calorie environments such as contest preparation. However they shouldn’t detract from your consumption of minimally processed nutrient dense foods (e.g. plant-centric matter). Ensure you track any hidden fibres and polyols towards your total calories/carbohydrates and pay close attention to your gut health.
References
Edwards, C. A., Johnson, I. T., & Read, N. W. (1987). Do viscous polysaccharides slow absorption by inhibiting diffusion or convection? European Journal of Clinical Nutrition, 41(10), 651-659.
EFSA Panel on Food Additives and Nutrient Sources (2013). Scientific opinion on the re-evaluation of aspartame (E 951) as a food additive. EFSA Journal, 11(12), 3496.
Fernstrom, J. D. (2018). Update on sweeteners and health. Nutrition Today, 53(4), 153-157.
Grabitske, H. A., & Slavin, J. L. (2009). Gastrointestinal effects of low-digestible carbohydrates. Critical Reviews in Food Science and Nutrition, 49(4), 327-360.
Hull, S. M., Re, R., Chambers, L., Echaniz, A., & Wickham, M. S. J. (2012). The effect of a mid-morning snack on glucose metabolism and satiety. Nutrition Journal, 11, 36.
Magnuson, B. A., Roberts, A., & Nestmann, E. R. (2016). Critical review of the current literature on the safety of sucralose. Food and Chemical Toxicology, 106, 324-355.
Magnuson, B. A., Carakostas, M. C., Moore, N. H., Poulos, S. P., & Renwick, A. G. (2017). Biological fate of low-calorie sweeteners. Nutrition Reviews, 74(11), 670-689.
Peters, J. C., Beck, J., Cardel, M., et al. (2014). The effects of water and non-nutritive sweetened beverages on weight loss. Obesity, 22(6), 1415-1421.
Roberfroid, M. (2008). Prebiotics: Concept, definition, criteria, methodologies, and products. The American Journal of Clinical Nutrition, 73(2 Suppl), 361S-364S.
Rogers, P. J., Appleton, K. M., Hajek, P., et al. (2016). Does low-energy sweetener consumption affect energy intake and body weight? International Journal of Obesity, 40(3), 381-394.
Schiffman, S. S., & Nill, S. (2023). Sucralose-6-acetate: A toxicological evaluation. Journal of Toxicology and Environmental Health, Part B, 26(2), 50-62.
Slavin, J. (2013). Fiber and prebiotics: Mechanisms and health benefits. Nutrients, 5(4), 1417-1435.
Suez, J., Cohen, Y., Valdés-Mas, R., et al. (2022). Personalized microbiome-driven effects of non-nutritive sweeteners on human glucose tolerance. Cell, 185(18), 3307-3328.e19.
Witkowski, M., Nemet, I., Alamri, H., et al. (2023). The artificial sweetener erythritol and cardiovascular event risk. Nature Medicine, 29(4), 710-718.
World Health Organization. (2023). WHO guidelines on non-sugar sweeteners. Geneva: World Health Organization.
Fazzino, T. L., Courville, A. B., Guo, J., & Hall, K. D. (2023). Ad libitum meal energy intake is positively influenced by energy density, eating rate, and hyper-palatable food across four dietary patterns. Nature Food, 4(1), 75-82. https://doi.org/10.1038/s43016-022-00688-4
