body
Appetite Increase (Undesired)
Adverse effectAppetite increase is an undesired body effect in which a person notices stronger or more frequent hunger, or a greater desire to eat. It describes the appetite sensation itself, not necessarily a measured change in food intake or body weight.
Appetite increase is classified as an undesired body effect, offering a clear label for this type of response.
These are research findings, not promises. Most options have little evidence, and results differ from person to person.
What can cause it
How likely each one is to cause it, most likely first.
FastingpracticeUnclear
Based on 7 studies. Strongest study: a pooled analysis of several trials.
Pooled analyses whose designs were not recorded reported hunger in studies of fasting. The findings do not quantify how often it occurred.
Open the Fasting pageCyclingpracticeUnclear
Based on one study. Strongest study: a randomized controlled trial.
Open the Cycling pageCardiopracticeUnclear
Based on one study.
Burning extra energy can increase hunger in some people, who may eat back some of the calories; this compensatory eating can slow weight loss.
Open the Cardio page
The expert view shows every study, dose protocol and source.
What can cause it
Interventions reported to bring this on3 listedHighest probability
- →PracticesFastingCertaintyLowSourceClinical7 other sources
Pooled analyses whose designs were not recorded reported hunger in studies of fasting. The findings do not quantify how often it occurred.
- →PracticesCyclingCertaintyLowSourceClinical1 other source
In a randomized trial of 12 people, hunger ratings were higher in evening than morning trials (46 ± 29 vs. 39 ± 28 mm) and in fasted than fed trials (48 ± 30 vs. 38 ± 27 mm).
Who was studied
- People with a condition
Open CyclingStudy result
Hunger ratings (100 mm VAS) were higher in the evening trials compared to the morning (46 ± 29 vs. 39 ± 28 mm) and higher in the fasted compared to the fed (48 ± 30 vs. 38 ± 27 mm).
- →PracticesCardioCertaintyLowSourceReference knowledge1 other source
Burning extra energy can increase hunger in some people, who may eat back some of the calories; this compensatory eating can slow weight loss.
Open CardioStudy result
Burning extra energy raises hunger in some people, who then eat back part of the calories (compensatory eating), which can slow weight loss.
How to read the evidence
Evidence tier — overall strength of the evidence for the whole compound
- StrongWell established — backed by strong, consistent human research.
- ModerateSome genuine support, but mostly from small or lower-quality studies. Promising, not proven.
- PreliminaryEarly-stage evidence — a promising hypothesis, not an established effect yet.
- LimitedVery limited evidence — treat this as a hypothesis, not proof.
- InsufficientNot enough good evidence to draw conclusions yet.
Certainty — how sure we can be that the effect is real
- Very highVery sure — strong, consistent evidence
- HighFairly sure — consistent evidence from good studies
- MediumModerately sure — new studies could change this
- LowNot sure — little or mixed evidence
- Very lowVery unsure — almost no usable evidence
Source — where the data comes from
- Meta-analysisPooled analysis of many trials — the strongest evidence
- RCTRandomized controlled trial — a strong human study design
- ClinicalA human clinical study
- Reference knowledgeFrom general health-science or pharmacology references, not a study of this exact claim
- Animal researchStudied in animals, not humans
- Community reportsAggregated user reports — anecdotal signal, not evidence
- TheoreticalMechanism-based reasoning, not yet tested
Study grade — quality of each underlying study (A best, D weakest)
- AHigh-quality — strong, consistent human trials
- BGood — solid evidence with some limitations
- CModerate — limited, small, or mixed-quality studies
- DWeak — preliminary, indirect, or animal-only
Confidence — how strongly the sources back a finding
A 0–100 score from study quality and agreement
Most supplement evidence is graded C–D. Read it as preliminary signal, not proof.
Full write-up
What is it
Appetite increase is an undesired body effect in which a person notices stronger or more frequent hunger, or a greater desire to eat. It describes the appetite sensation itself, not necessarily a measured change in food intake or body weight. This response has been reported in connection with interventions such as L-Leucine and CBD (Cannabidiol), but it is not an intended benefit in this context.
How interventions help
This outcome covers several related but distinct changes: a stronger subjective feeling of hunger, increased appetite, and increased oral intake. These should not be treated as identical measures. A person may notice more hunger without a confirmed increase in intake, while an increase in intake describes eating behavior more directly.
The interventions associated with this outcome span exercise, amino-acid supplements, botanical extracts, and other supplements. Their findings are not necessarily interchangeable because they may reflect different ways of assessing appetite, from a reported sensation to observed eating behavior. Cycling findings also varied with the circumstances in which it was performed, indicating that timing and whether someone had eaten may affect hunger ratings in that setting.
Some associations come from human clinical research, while others are based on personal reports or reviews. These evidence types provide different kinds of information and should not be interpreted as equally reliable or as showing that appetite will increase for everyone. The findings also do not establish a common dose, duration of use, onset, or whether the change continues after an intervention is stopped. Appetite-related effects may therefore depend on the intervention, the situation in which it is used, and how the outcome is measured.
Choosing guidance
When choosing among these options, distinguish formal clinical evidence from anecdotal reports. Clinical evidence comes from several study designs, including randomized controlled trials, systematic reviews, a pilot study, and a narrative review. Anecdotal evidence instead reflects reports from online communities or videos, so it is better suited to readers who want to be aware of reported experiences rather than rely on formal human research.
The clinical findings generally come from studies where health status was not specified. Cycling was examined in a clinical-condition context, so its findings may not apply in the same way to people outside that context. This distinction matters when considering whether an observation is relevant to a particular person.
The available information does not establish how much of any option was taken, how long it was used, or how quickly appetite changes appeared. It also does not provide direct head-to-head comparisons or show whether studies disagreed. As a result, the options cannot be meaningfully separated here by speed, duration, amount, or consistency of findings. Readers prioritizing formal human evidence may focus on the clinically studied options, while those considering options supported only by anecdotal reports should treat them as less established observations.