16:6 Time-Restricted Eating Lowered a Key Inflammation Marker in Women With Obesity: What the Research Shows

16:6 Time-Restricted Eating Lowered a Key Inflammation Marker in Women With Obesity: What the Research Shows

Medical disclaimer: This article summarises published research for informational purposes only. It is not medical advice and is not a substitute for guidance from a qualified health professional. Always consult your doctor before starting any fasting protocol, especially if you have an existing health condition or take medication.

Study at a Glance

What This Study Looked At

Obesity is linked to chronic low-grade inflammation — elevated pro-inflammatory signals like interferon-gamma (IFN-γ) alongside blunted anti-inflammatory signals like interleukin-10 (IL-10). This study asked a narrow, useful question: over just 20 days, does time-restricted eating or alternate-day fasting actually move these two cytokines in young women with obesity, or is the anti-inflammatory reputation of fasting bigger than the short-term evidence supports?

Who Was Studied

Participant profile: 23 non-diabetic women aged 18–25 with obesity (BMI ≥ 25 kg/m² by the Asia-Pacific classification), recruited in Indonesia.

How the protocols worked in this study: The TRE group compressed all food intake into a 6-hour window each day. The ADMF group alternated a heavily calorie-restricted "fast day" with a normal "feed day" across the 20-day period. Blood was drawn before and after the intervention to measure serum IFN-γ and IL-10 by ELISA.

What the Researchers Found

Interferon-gamma (pro-inflammatory)

• Only the TRE 18:6 group showed a statistically significant drop in the pro-inflammatory marker IFN-γ.
• ADMF, despite its more aggressive calorie restriction on fast days, did not produce a significant change in either cytokine over this short window.

Interleukin-10 (anti-inflammatory)

• IL-10 levels did not change significantly in any of the three groups — TRE, ADMF, or control.
• This means the anti-inflammatory effect seen with TRE was not explained by IL-10 going up; IL-10 stayed roughly flat.

What Did Not Change

• IL-10 in the TRE group, the ADMF group, or the control group
• IFN-γ in the ADMF and control groups
• No adverse events were reported in either fasting group over the 20-day period

What the Researchers Concluded

The researchers concluded that time-restricted eating reduced the pro-inflammatory cytokine IFN-γ without significantly altering the anti-inflammatory cytokine IL-10 — suggesting that TRE's short-term anti-inflammatory effect works by dialing down a pro-inflammatory signal rather than by boosting an anti-inflammatory one. Alternate-day modified fasting showed no measurable immunomodulatory effect on either marker in this timeframe.

What This Means If You Fast

• Time-restricted eating showed a real, measurable effect in just 20 days. An 18:6 window (6 hours of eating, 18 hours fasting) lowered a genuine marker of inflammation in women with obesity in under three weeks — you don't necessarily need months to see biological change.
• Not every fasting protocol works the same way. ADMF, often seen as the "stronger" intervention because of its calorie restriction on fast days, didn't outperform TRE here — a reminder that longer or harder isn't automatically better for every biomarker. See our guide on choosing the right protocol.
• "Anti-inflammatory" doesn't always mean the same mechanism. This study is a useful check on the assumption that fasting reduces inflammation by boosting IL-10 — here it didn't. The benefit may be running through suppressing pro-inflammatory signaling instead.
• This is early-stage evidence, not a green light for aggressive fasting. Twenty days in 23 young, otherwise-healthy women with obesity is a starting point, not a guarantee for everyone. If you're managing an inflammatory or autoimmune condition, read our piece on fasting and autoimmune conditions before making changes.
• Small effects in small studies deserve modest expectations. One significant p-value in one cytokine, in one small group, is a signal worth watching — not proof that fasting "cures inflammation."

Study Limitations

• Very small sample size — only 7–8 women per group
• Short duration (20 days) — no data on whether effects persist or grow over months
• Only two cytokines were measured; a fuller inflammatory panel (CRP, TNF-α, IL-6) would give a more complete picture
• Participants were young (18–25), Asian, and female — findings may not generalize to men, older adults, or other ethnic groups
• "Quasi-experimental" design with pretest-posttest control groups is not a fully randomized controlled trial, which limits how confidently the results can be attributed to the intervention alone
• No PMID could be confirmed at the time of writing due to a network access issue; readers should verify via the DOI link before citing this study elsewhere

Source

Rejeki, P.S. et al. (2025). The Effects of Time-Restricted Eating and Alternate-Day Modified Fasting on Interferon-γ and Interleukin-10 Levels in Young Asian Women with Obesity: A Quasi-Experimental Study. Immuno, 5(3), 39. DOI: 10.3390/immuno5030039

Frequently Asked Questions

Does intermittent fasting lower inflammation markers?

In this study, an 18:6 time-restricted eating window significantly lowered IFN-γ, a pro-inflammatory cytokine, in just 20 days — but the anti-inflammatory marker IL-10 did not change. Fasting's anti-inflammatory effect appears to work through more than one pathway, and not every marker moves at once.

Is time-restricted eating better than alternate-day fasting for inflammation?

In this specific 20-day trial, yes — TRE 18:6 produced a significant reduction in IFN-γ while alternate-day modified fasting did not show a significant change in either cytokine measured. That doesn't mean ADMF has no anti-inflammatory effect generally, just that it didn't show one here in this short window.

How long does it take for intermittent fasting to reduce inflammation?

This study found a significant change in IFN-γ after just 20 days of an 18:6 eating window, suggesting some inflammatory changes can appear relatively quickly. Other inflammatory markers may take longer, and results vary by individual health status.

Does fasting increase IL-10?

Not according to this study — IL-10 levels stayed statistically unchanged in all three groups (TRE, ADMF, and control) over the 20-day period. Any anti-inflammatory benefit from TRE in this study came from lowering IFN-γ, not raising IL-10.

Is this study relevant to men or people who aren't obese?

Not directly. This trial only included women aged 18–25 with obesity, so the findings can't be assumed to apply to men, older adults, or people at a healthy weight without further research.

Related Research and Articles

• Does Intermittent Fasting Reduce Inflammation?
• Fasting and Inflammation: What Women Should Know
• Intermittent Fasting and Autoimmune Conditions in Women
• What Is the 18:6 Intermittent Fasting Method?
• Alternate Day Fasting for Women: Is It Safe?
• How to Choose Your Fasting Protocol

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