What is the relationship between artificial sweeteners (AS) and the risk of type 2 diabetes (T2D)?

Relationship Between Artificial Sweeteners and Type 2 Diabetes Risk

The evidence suggests artificial sweeteners are associated with an increased risk of type 2 diabetes, though this relationship is confounded by reverse causation and residual confounding, making water or unsweetened beverages the preferred alternative to sugar-sweetened drinks rather than artificial sweeteners.

The Complex Evidence Landscape

The relationship between artificial sweeteners and type 2 diabetes is characterized by conflicting evidence across different study types:

Observational Studies Show Increased Risk

Meta-analyses of prospective cohort studies demonstrate that higher consumption of artificially sweetened beverages is associated with increased type 2 diabetes incidence:

• Each additional serving per day of artificially sweetened beverages increases diabetes risk by 25% (95% CI: 18-33%) before adjustment for adiposity, and 8% (95% CI: 2-15%) after adjustment for body weight 1
• Analysis adjusted for initial BMI found a 0.08 increase in risk for each serving of artificially sweetened beverage, compared to 0.13 for sugar-sweetened beverages 1
• The pooled relative risk for obesity in individuals consuming artificially sweetened soda was 1.59 (95% CI: 1.22-2.08) 1

Critical Confounding Factors

The observed associations are heavily influenced by reverse causation and confounding:

• People who are obese or developing diabetes are more likely to use artificial sweeteners as a compensatory behavior 1
• Early stages of type 2 diabetes are characterized by increased fluid consumption, which may explain part of the association with artificially sweetened drinks 1
• Substantial heterogeneity exists across studies, making interpretation difficult 1

Current Guideline Recommendations

American Diabetes Association Position (2021)

The ADA acknowledges FDA approval of nonnutritive sweeteners but provides nuanced guidance:

• Nonnutritive sweeteners may be an acceptable substitute for nutritive sweeteners when consumed in moderation for those accustomed to sugar-sweetened products 1
• They do not appear to have significant effects on glycemic management 1
• They can reduce overall calorie and carbohydrate intake, but only if individuals do not compensate with additional calories from other sources 1
• Mixed evidence exists regarding weight management, with some studies showing benefit and others showing association with weight gain 1

American Heart Association Guidance (2020)

The AHA Nutrition Committee reviewed cardiometabolic outcomes and concluded:

• Use of alternatives to sugar-sweetened beverages, with focus on plain, carbonated, or unsweetened flavored water, should be encouraged over artificially sweetened beverages 1
• Prolonged consumption of low-calorie sweetened beverages by children is not advised due to limited evidence on adverse health effects 1
• For those habituated to sweet-tasting beverages, replacing sugar-sweetened beverages with artificially sweetened versions may provide a first step, but water or unsweetened beverages are strongly encouraged 1

American College of Cardiology/American Heart Association (2023)

The most recent cardiovascular guidelines state:

• Recommendations are unavailable for artificial sweeteners because of limited data in populations with chronic coronary disease 1
• This represents a cautious stance given the lack of definitive evidence for cardiovascular outcomes

Practical Clinical Algorithm

Step 1: Assess Current Beverage Consumption Pattern

• Identify patients consuming sugar-sweetened beverages regularly (>1 serving/day)
• Determine if patient is already using artificial sweeteners and frequency of consumption
• Evaluate for obesity, prediabetes, or established type 2 diabetes 1

Step 2: Primary Recommendation Strategy

For all patients, regardless of diabetes status:

• First-line recommendation: Replace all sweetened beverages (both sugar-sweetened and artificially sweetened) with water, unsweetened tea, or unsweetened coffee 1
• Emphasize water intake as the preferred beverage 1

Step 3: Transitional Strategy (If Needed)

For patients who refuse to eliminate sweet-tasting beverages entirely:

• Artificially sweetened beverages may serve as a short-term replacement strategy only 1
• Set explicit timeline for transition (e.g., 3-6 months) before moving to unsweetened options
• Monitor for compensatory calorie intake from other food sources 1

Step 4: Special Population Considerations

Children and adolescents:

• Prolonged consumption of artificially sweetened beverages is not advised 1
• Focus on establishing water as primary beverage early in life

Patients with established type 2 diabetes:

• Artificial sweeteners are FDA-approved and may be used in moderation 1
• Do not expect glycemic benefit from artificial sweeteners alone 1
• Prioritize overall dietary pattern changes over isolated sweetener substitution

Common Pitfalls and How to Avoid Them

Pitfall 1: Assuming Artificial Sweeteners Are "Healthy" Alternatives

The evidence does not support artificial sweeteners as health-promoting:

• While they reduce calories, they do not provide metabolic benefits beyond calorie reduction 1
• Observational data suggests potential harm, though causality is uncertain 1
• Avoid framing artificial sweeteners as a positive dietary change; instead, frame them only as potentially less harmful than sugar-sweetened beverages in the short term 1

Pitfall 2: Ignoring Compensation Behaviors

Patients may unconsciously compensate for "saved" calories:

• Artificial sweeteners only reduce calorie intake if patients do not consume additional calories from other sources 1
• Explicitly counsel patients about this phenomenon and monitor total calorie intake
• The addition of nonnutritive sweeteners without energy restriction provides no benefit for weight loss 1

Pitfall 3: Overlooking Publication Bias

The literature on artificial sweeteners contains significant publication bias and residual confounding:

• Meta-analyses have noted these limitations explicitly 1
• Industry funding may influence study outcomes 1
• Base recommendations on the most conservative interpretation of available evidence, which favors water over artificial sweeteners 1

Pitfall 4: Failing to Address the Root Cause

Artificial sweeteners maintain preference for sweet taste:

• They do not help patients reduce their overall preference for sweetness
• Focus on taste adaptation strategies that gradually reduce sweetness preference across the entire diet 1

Nuances in the Evidence

Why Observational Studies May Overestimate Risk

The association between artificial sweeteners and diabetes in observational studies likely reflects:

• Reverse causation: people at high risk for diabetes preferentially choose artificial sweeteners 1
• Confounding by indication: obesity and metabolic dysfunction drive both artificial sweetener use and diabetes risk 1
• Detection bias: people using artificial sweeteners may have more frequent medical monitoring

Why Short-Term Trials May Underestimate Risk

Intervention studies showing neutral or beneficial effects have limitations:

• Short duration (weeks to months) may miss long-term metabolic effects 1
• Small sample sizes lack statistical power 1
• Participants unblinded to treatment groups 1
• Potential conflicts of interest in research funding 1

Bottom Line for Clinical Practice

Given the conflicting evidence and potential for harm, the safest approach is to discourage both sugar-sweetened and artificially sweetened beverages in favor of water and unsweetened beverages 1. For patients who absolutely refuse to eliminate sweet-tasting beverages, artificial sweeteners may be used as a temporary bridge, but this should be explicitly framed as a short-term compromise rather than a long-term solution 1. The goal remains complete transition to unsweetened beverages to reduce diabetes risk and promote overall metabolic health 1.