Sugar vs. Sweeteners: Benefits, Risks, and What the Science Really Says

Sugar is everywhere in our diets, from natural sources like fruit to processed forms like table sugar (sucrose) and high-fructose corn syrup. Many people turn to alternatives—natural (stevia, monk fruit) or artificial (aspartame, sucralose, saccharin, advantame)—to cut calories, manage blood sugar, or satisfy a sweet tooth. But are these swaps truly healthier? Here's a balanced look at the science, including benefits and risks for both sugar and common sweeteners.

Table Sugar (Sucrose) and Processed Sugars

• Benefits: Provides quick energy (4 kcal/g), enhances flavor, and supports short-term performance in endurance activities. Natural sources (e.g., fruit) come with fiber, vitamins, and antioxidants.

• Risks: High intake is strongly linked to weight gain, insulin resistance, type 2 diabetes, fatty liver, inflammation, and increased cardiovascular disease risk. Excess fructose (common in processed sugars) is particularly problematic for liver health and metabolic syndrome.

Bottom line: Moderation is key. The American Heart Association recommends ≤25g added sugar/day for women and ≤36g for men. Most health issues stem from overconsumption, not small amounts.

Natural Sweeteners

These are plant-derived and often marketed as "clean" alternatives.

• Stevia (from Stevia rebaudiana leaves, steviol glycosides):

  • Benefits: Zero calories, zero glycemic index, doesn't raise blood sugar or insulin. Some studies suggest antioxidant properties and potential blood pressure/glucose benefits.

  • Risks: Generally safe (FDA GRAS status). Mild GI upset or bitter aftertaste in some people. No major long-term concerns in humans.

• Monk Fruit (Luo Han Guo extract, mogrosides):

  • Benefits: Zero calories, zero GI, antioxidant effects from mogrosides. Often considered the "cleanest" natural option with no reported side effects.

  • Risks: Very safe (FDA GRAS). Limited long-term studies, but no red flags. Some products blend with erythritol, which has its own concerns (see below).

Bottom line: Stevia and pure monk fruit are among the safest and healthiest swaps for sugar, with no calories and minimal metabolic impact.

Artificial Sweeteners

These are lab-made, high-intensity options (100–20,000× sweeter than sugar).

• Aspartame (Equal, NutraSweet):

  • Benefits: Zero calories, doesn't raise blood sugar.

  • Risks: Classified by IARC (WHO) as "possibly carcinogenic" (Group 2B) in 2023 based on limited evidence for liver cancer. JECFA/WHO reaffirmed safety within ADI (40 mg/kg body weight/day). No strong human evidence for cancer at typical doses.

• Sucralose (Splenda):

  • Benefits: Zero calories, heat-stable for cooking, no blood sugar impact.

  • Risks: Some studies show potential gut microbiome changes. Generally considered safe by FDA/EFSA.

• Saccharin (Sweet'N Low):

  • Benefits: Zero calories, no blood sugar effect.

  • Risks: Old rat studies linked to bladder cancer (delisted from carcinogen list). Safe for humans per FDA.

• Advantame:

  • Benefits: Extremely potent (20,000× sweeter), low calorie.

  • Risks: Very limited data, but FDA-approved as safe.

Bottom line: Artificial sweeteners are safe within approved limits (ADI). No convincing evidence of cancer or major harm at normal consumption. Some concern for gut health or metabolic effects in sensitive people.

Sugar Alcohols (Polyols)

These provide 0–3 kcal/g and are popular in keto/low-carb products.

• Xylitol: Benefits (dental health, low GI). Risks (GI upset, possible CV concerns in high doses per recent studies).

• Erythritol: Benefits (zero GI, well-tolerated). Risks (2023–2024 studies link high blood levels to increased clotting and CV events like heart attack/stroke).

• Sorbitol: Benefits (low GI). Risks (GI issues like bloating/diarrhea in higher amounts).

Bottom line: Sugar alcohols are generally safe in moderation, but erythritol and xylitol have emerging CV risk signals—limit if concerned.

Key Takeaways for Athletes & Longevity

• Sugar: Limit added/processed forms. Use natural sources (fruit) sparingly.

• Best swaps: Stevia or pure monk fruit for zero-calorie sweetness with minimal risk.

• Artificial options: Safe in moderation, but not a free pass for unlimited diet soda.

• Sugar alcohols: Fine occasionally, but watch erythritol intake due to recent CV data.

The best approach? Reduce overall sweetness reliance. Small amounts of any sweetener are unlikely to harm, but excess sugar (or over-relying on substitutes) can disrupt taste preferences and health.