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Randomized trial · measured the question itself

3-month trial in 160 adults: mixed results for fasting plans versus a Mediterranean diet

Martínez-Montoro and colleagues · BMC medicine · 2025

Original title: Effect of a ketogenic diet, time-restricted eating, or alternate-day fasting on weight loss in adults with obesity: a randomized clinical trial.

Under review. A person has not yet checked this summary against the paper. It is written from the PubMed abstract. Until a person checks it, search engines are asked not to list this page.

What the study found

Mixed

Vs the calorie-limited Mediterranean diet, weight change differed by - 3.14 kg (- 4.98 to - 1.30 kg) with alternate-day fasting and - 2.27 kg (- 4.13 to - 0.40 kg) with late window, but not early window (- 1.22 kg (- 3.07 to 0.64 kg)).

The study at a glance

Type of study
Randomized trial
Who or what was studied
160 people · adults with obesity, average age 45.7
What was tested
modified alternate-day fasting, early or late time restricted eating, or keto diet, all with calorie limits, vs a calorie-limited Mediterranean diet, for 3 months
What it measured
The question itself: weight loss, compared with ordinary calorie cutting
How long
12 weeks
Trial registration
NCT04453150
Who has a stake
No stake declared
No competing interests declared.
Journal
BMC medicine, 2025
Source
PubMed record 40598397. This page is based on the abstract only.

How much this study counts

  • ✓Randomized: people were put into groups by chance, so the groups start out alike.
  • •Medium size: 160 people.
  • •Lasted 12 weeks.
  • ✓Measured the question itself: weight loss, compared with ordinary calorie cutting.
  • ✓No competing interests declared.
  • •Summarized from the PubMed abstract only. The full paper may hold details the abstract leaves out.

✓ Strength– Limit• Note

These points come from fixed rules about the type of study, its size and length, what it measured, and who has a stake. Every study on Digestery gets the same rules.

Where this study sits

Each dot is one on-topic paper on this question. Steps near the top answer the question more directly.

↑ Stronger evidence

  1. Trials in people: weight loss

    9

    5 benefit, 2 mixed, 2 no difference

    ↑ This study is the ringed dot

  2. Trials in people: other measures

    8

    4 benefit, 3 mixed, 1 no difference

  3. Trials in people: lab tests or safety

    1

    1 benefit

  4. Population studies

    0

    None among the papers we read.

  5. Blood levels and genes

    0

    None among the papers we read.

↓ Weaker evidence

  • Points to benefit
  • Mixed
  • No difference
  • No direction
  • Points to harm

How it fits with the other research

The short answer to “Does intermittent fasting help with weight loss?”

Yes, but about like calorie cutting.

Confidence: moderate. Based on 26 on-topic papers.

Read the full answer

Of the other 8 papers on the same step: 5 benefit, 1 mixed, 2 no difference. This one found mixed. It differs from most of them.

Other papers on the same step

See all 26 studies on this question

How this page was made

Label

First read of the abstract
Claude Sonnet
Independent second read
Claude Haiku
Differences settled
The reviewer corrected 2 fields after reading the abstract. Claude Opus 5.5.
Headline
Claude Sonnet, from the checked study record. A script checked its numbers and wording.
Numbers
Checked against the abstract by a script
“How much this study counts”
Fixed rules, the same for every study
Source check by a person
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