Nutrition · Limited evidence

Ultra-Processed Foods Lead to Eating More

When meals were matched for macronutrients, an ultra-processed diet led participants to eat roughly 500 kcal more per day and gain weight.

Inpatient randomized crossover trial · 1 source · 2 min

What the studies show

  • The ultra-processed diet led to higher intake and weight gain over two weeks.
  • The unprocessed diet led to weight loss over the same period.
  • The effect occurred even though offered macronutrients, sugar, sodium, and fiber were similar.

How Letz applies it

The meal planner pantry classifies each food by its degree of processing (NOVA): whole foods form the base of meals, ultra-processed foods serve as complements, and photo logging flags when the day was dominated by them.

Numbers derived from this rule

ParameterRangeWeightRule
Fiber12–16 g per 1000 kcal50%About 14 g of fiber per 1000 kcal, which amounts to 25 to 29 g per day for most adults.Fiber and Carbohydrate Quality · Ultra-Processed Foods Lead to Eating More

Who it applies to

Adults with unrestricted access to food; effect on spontaneous intake.

Limits

Short and small study; does not identify which ultra-processed foods are worse, nor does it rule out the role of preference and convenience.

Sources

More in Nutrition

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