Among teenage boys with fatty liver disease, cutting added sugars to less than 3% of daily calories led to an average improvement in heart health markers over eight weeks, but this improvement was not clearly better than what happened in boys who kept eating normally.
Evidence from Studies
No evidence studies found yet.
What Would Prove This
Per GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this claim, ordered from strongest to weakest.
Whether restricting free sugar to <3% of calories consistently improves cardiovascular health scores in adolescents with MASLD across multiple high-quality RCTs, accounting for heterogeneity in diet composition, duration, and baseline health.
A systematic review and meta-analysis of all randomized controlled trials comparing a free-sugar-restricted diet (<3% of calories) to a control diet in adolescents aged 11–16 with confirmed MASLD, using Life’s Essential 8 as the primary outcome, with minimum 8-week duration, intention-to-treat analysis, and adjustment for age, ethnicity, and energy intake. Studies must report standardized CVH metrics and be published in peer-reviewed journals.
Whether a low-free-sugar diet directly causes a greater improvement in cardiovascular health scores compared to a control diet in adolescent boys with MASLD, when properly blinded and powered.
A double-blind, placebo-controlled RCT with 150+ adolescent boys aged 11–16 with MASLD, randomized to either a study-provided diet with <3% free sugar (using sugar-free substitutes matched for taste and texture) or a control diet with typical sugar intake (10–15%), delivered over 16 weeks, with primary outcome being change in Life’s Essential 8 score, secondary outcomes including liver fat, lipids, and insulin sensitivity, measured by DXA and MRI.
Whether adolescents with naturally low free-sugar intake over time have better cardiovascular health trajectories than those with higher intake, adjusting for confounders like physical activity and socioeconomic status.
A prospective cohort following 500 adolescent boys and girls with MASLD for 3 years, measuring dietary sugar intake via repeated 24-hour recalls and food diaries, and tracking annual changes in Life’s Essential 8 scores, adjusting for BMI, physical activity, and parental education.
Whether adolescents with the worst cardiovascular health scores are more likely to have had high free-sugar intake in the prior year compared to those with better scores.
A case-control study comparing 100 adolescents with MASLD and low CVH scores (<50) to 100 with high CVH scores (>80), retrospectively assessing free-sugar intake over the prior 12 months using validated food frequency questionnaires and biomarkers (e.g., urinary sucrose).
Whether there is a statistical association between current free-sugar intake and current cardiovascular health scores in adolescents with MASLD at a single point in time.
A cross-sectional survey of 300 adolescents with MASLD measuring daily free-sugar intake via 3-day food records and assessing CVH score using Life’s Essential 8 metrics on the same day, adjusting for age, sex, and BMI.