For people with a certain gene combination, eating broccoli for two weeks actually made one inflammation marker go up instead of down.

Scientific Claim

In healthy young adults aged 20–40 with the GSTM1-null/GSTT1-null genotype, consumption of 7 g/kg body weight of cruciferous vegetables per day for 14 days increases serum interleukin-6 (IL-6) by 22%, indicating a paradoxical pro-inflammatory effect in this genetic subgroup.

Original Statement

“Geometric mean IL-6 concentrations were significantly higher among individuals who were both GSTM1-null and GSTT1-null [Change, %: 21.8 (1.0, 73.0)] with the 1xC diet compared with the basal diet.”

From study:Cruciferous vegetables have variable effects on biomarkers of systemic inflammation in a randomized controlled trial in healthy young adults.

Evidence Quality Assessment

Claim Status

appropriately stated

Study Design Support

Design supports claim

Appropriate Language Strength

definitive

Can make definitive causal claims

Assessment Explanation

The RCT design with genotype-stratified analysis and statistical significance (p<0.05) supports definitive causal language for this specific subgroup and intervention.

Evidence from Studies

Supporting (0)

No supporting evidence found

Contradicting (1)

Cruciferous vegetables have variable effects on biomarkers of systemic inflammation in a randomized controlled trial in healthy young adults.

Randomized Controlled Trial

Human

The study found that eating lots of broccoli and similar veggies actually lowered a marker of inflammation (IL-6) in most people, including those with the specific gene type mentioned — the opposite of what the claim says.

Source Study

Cruciferous vegetables have variable effects on biomarkers of systemic inflammation in a randomized controlled trial in healthy young adults.

Score: 69

DOI: 10.3945/jn.114.197434

Similar Assertions

Eating a moderate amount of broccoli for two weeks might lower inflammation in some people with a certain gene, but the effect isn't strong enough to be sure yet.

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Eating a lot of broccoli, cabbage, and similar veggies every day for two weeks can lower a key inflammation marker in the blood of healthy young people.

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People with a specific genetic variation who eat a mix of broccoli and carrots for two weeks see big drops in two key inflammation markers in their blood.

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Eating a mix of broccoli and carrots every day for two weeks lowers a blood inflammation marker just as much as eating a lot of broccoli alone.

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People with a certain gene variation who eat a lot of broccoli for two weeks see lower levels of two inflammation markers in their blood.

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