In a large Iranian study, people who ate more carotenoids (plant pigments found in colorful produce) were less likely to be overweight or have obesity.
In a large Iranian study, people who ate more carotenoids (plant pigments found in colorful produce) were less likely to be overweight or have obesity.
Researchers looked at whether eating more carotenoids—natural pigments that give many fruits and vegetables their red, orange, and dark-green colors—was linked with body weight. They analyzed diet and health information from 4,202 adults ages 35 to 70 in Sabzevar, Iran. Participants reported what they typically ate using a detailed food questionnaire, and researchers compared carotenoid intake across people with normal weight, overweight, and obesity.
Overall, carotenoid intake was highest in the normal-weight group and lowest in the obesity group. Well-known carotenoids such as beta-carotene, lutein/zeaxanthin, and lycopene showed this same pattern. When the researchers accounted for factors like age, sex, education, physical activity, and total calories, higher carotenoid intake was still linked with lower odds of being overweight or having obesity.
For older adults, this supports a practical message: regularly eating a variety of colorful fruits and vegetables may be one helpful part of a weight-friendly eating pattern, alongside staying active and managing overall portions.
Use the full description to understand the study design, methods, and the limits of the findings.
A more detailed explanation of the study including:
Study design and methodology (in simple terms): This was a cross-sectional study (a “snapshot in time”). Researchers used existing data from a large community cohort in Iran. Adults ages 35–70 had their height and weight measured to calculate BMI, and trained nutritionists interviewed them using a 237-item food frequency questionnaire to estimate usual intake of several carotenoids. Carotenoid intake was adjusted for total calories (reported as micrograms per 1,000 calories) to better compare diets.
Key findings (with numbers): Total carotenoids were lower in the obesity group (about 12,792 µg/1,000 kcal) than in the normal-weight group (about 14,250 µg/1,000 kcal). In statistical models adjusting for lifestyle and demographics, higher total carotenoid intake was linked with lower odds of overweight (energy-adjusted OR 0.647; 95% CI 0.429–0.975) and lower odds of obesity (energy-adjusted OR 0.395; 95% CI 0.244–0.640). Several individual carotenoids (including beta-carotene, lutein/zeaxanthin, and lycopene) also tended to be lower in people with obesity.
Limitations/caveats: Because this study measured diet and weight at the same time, it cannot prove that carotenoids cause weight loss. Food questionnaires can be imperfect (people may forget or underestimate foods). Also, results from one region and dietary pattern may not apply to everyone.
Practical implications for daily life: Carotenoids come from foods like leafy greens (spinach, kale), tomatoes, carrots, sweet potatoes, peppers, and oranges. A simple goal is to include multiple colors of produce most days. These foods may support overall health and can replace more calorie-dense choices, which may help with weight management over time.
If you are trying to manage weight, blood sugar, heart health, or take medications that affect diet, talk with your healthcare provider or a registered dietitian about the safest, most realistic plan for you.
Open the original publication for the complete methods, outcomes, and source material.
This study provides moderate-to-low quality evidence for seniors because it is cross-sectional: diet (carotenoid intake) and BMI were measured at the same time, so causality cannot be established and reverse causation is plausible. Methodological strengths include a relatively large sample, measured height/weight (reducing outcome measurement error), and multivariable adjustment including energy adjustment. Key limitations affecting reliability are self-reported dietary intake via a long FFQ (measurement error and reporting bias), likely residual confounding (overall dietary pattern, health status, medications, socioeconomic factors), and limited senior-specific applicability because the cohort spans ages 35–70 without clear 60+ focused analyses. Overall, the findings are useful for hypothesis generation and supportive of general dietary guidance, but they should not be treated as strong evidence that carotenoids themselves reduce overweight/obesity risk in adults 60+.
| Category | Score | Rating |
|---|---|---|
| Study Design / Evidence Level | 4.0/10 | |
| Bias & Methods | 5.0/10 | |
| Statistical Integrity | 6.0/10 | |
| Transparency | 6.0/10 | |
| Conflict of Interest Disclosure | 6.0/10 | |
| Replication / External Validation | 4.0/10 | |
| Relevance to Seniors | 4.5/10 | |
| Journal Quality | 7.0/10 |
Conservative scoring reflects: (1) observational cross-sectional design; (2) exposure measurement limitations (FFQ); (3) potential multiple-comparison issues across individual carotenoids; (4) uncertain availability of preregistration, code/data sharing, and detailed missing-data handling from the provided summary; (5) generalizability limits (single region/cultural dietary pattern). If the full text confirms robust sensitivity analyses (e.g., stratification by age/sex, adjustment for comorbidities/medications, correction for multiple testing, and clear COI/funding independence), several category scores could be revised upward.
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