Even though people still ate more calories than they burned, eating high-protein, low-carb ultra-processed foods made them much less likely to store excess energy as fat compared to normal-protein ultra-processed foods.
Scientific Claim
In healthy young adults, a short-term (54-hour) high-protein (30% energy), lower-carbohydrate (29% energy) ultra-processed diet improves energy balance by reducing net positive energy balance from 32% to 18% compared to a normal-protein, normal-carbohydrate ultra-processed diet, indicating a favorable shift in energy partitioning.
Original Statement
“Energy balance was lower with HPLC-UPF compared with NPNC-UPF (+18% versus +32% P < 0.001; Fig. 3c).”
Evidence Quality Assessment
Claim Status
appropriately stated
Study Design Support
Design supports claim
Appropriate Language Strength
definitive
Can make definitive causal claims
Assessment Explanation
Energy balance is a direct calculation from precisely measured intake and expenditure in a controlled RCT. The 14% reduction is statistically significant and quantified, justifying definitive language.
Gold Standard Evidence Needed
According to GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this specific claim, ordered from strongest to weakest evidence.
Systematic Review & Meta-AnalysisLevel 1aWhether the 14% reduction in positive energy balance from high-protein UPFs is consistent across different energy intakes and populations.
Whether the 14% reduction in positive energy balance from high-protein UPFs is consistent across different energy intakes and populations.
What This Would Prove
Whether the 14% reduction in positive energy balance from high-protein UPFs is consistent across different energy intakes and populations.
Ideal Study Design
A meta-analysis of 12+ RCTs using calorimetry to compare high-protein (≥25% energy) vs. normal-protein (≤15% energy) ultra-processed diets in healthy adults, reporting energy balance as % of intake, with subgroup analysis by sex, BMI, and duration.
Limitation: Cannot determine if this translates to long-term fat loss.
Randomized Controlled TrialLevel 1bIn EvidenceWhether this improved energy balance leads to measurable fat loss over 8–12 weeks.
Whether this improved energy balance leads to measurable fat loss over 8–12 weeks.
What This Would Prove
Whether this improved energy balance leads to measurable fat loss over 8–12 weeks.
Ideal Study Design
A double-blind RCT of 80 healthy adults randomized to 12 weeks of high-protein (30% energy) or normal-protein (13% energy) ultra-processed diets, with ad libitum intake, daily energy expenditure measured by DLW, and fat mass tracked via DXA.
Limitation: Does not assess metabolic adaptation or hormonal resistance over time.
Prospective Cohort StudyLevel 2bWhether habitual consumption of high-protein UPFs predicts lower fat mass gain over time.
Whether habitual consumption of high-protein UPFs predicts lower fat mass gain over time.
What This Would Prove
Whether habitual consumption of high-protein UPFs predicts lower fat mass gain over time.
Ideal Study Design
A 5-year prospective cohort of 4,000 adults tracking UPF intake (NOVA), protein content, and fat mass via DXA annually, adjusting for total energy intake, physical activity, and sleep.
Limitation: Cannot prove causation due to confounding by lifestyle and self-report bias.
Evidence from Studies
Supporting (1)
Short-term effects of high-protein, lower-carbohydrate ultra-processed foods on human energy balance
This study gave people two different ultra-processed diets for just over two days—one with more protein and less carbs—and found they ate less and burned more energy, leading to less excess calorie storage, exactly as the claim says.