Chlorophyll, Detox, and Gut Health

How wheatgrass supports digestion, reduces inflammation, lowers cholesterol, and provides dense antioxidant nutrition

Wheatgrass is the young, tender grass of the common wheat plant (Triticum aestivum), harvested just 7–10 days after sprouting before it develops any gluten. It is one of the most nutrient-dense green foods available — packed with chlorophyll, vitamins C and E, B vitamins, iron, calcium, magnesium, and a broad spectrum of antioxidant compounds including flavonoids and phenolic acids [2]. A single 30 mL shot of wheatgrass juice is equivalent nutritionally to roughly 1–1.5 kg of leafy vegetables. Clinical trials have confirmed meaningful benefits for gut inflammation and cholesterol, while animal and observational studies support its antioxidant and blood-building effects [1][4].

What Makes Wheatgrass Different

The defining characteristic of wheatgrass is its chlorophyll content. Chlorophyll — the green pigment responsible for photosynthesis — makes up roughly 70% of the solid content of wheatgrass juice. It is structurally almost identical to haemoglobin, with the key difference being that haemoglobin centres on an iron atom where chlorophyll centres on magnesium. This similarity has generated long-standing interest in chlorophyll as a blood-building nutrient.

Beyond chlorophyll, wheatgrass is rich in:

Superoxide dismutase (SOD): A powerful antioxidant enzyme that neutralises the superoxide radical, a primary driver of oxidative stress and cellular aging.
P4D1: A glycoprotein unique to wheatgrass that has shown anti-inflammatory and DNA-repair activity in laboratory settings.
Vitamins C and E: Both fat- and water-soluble antioxidants working synergistically.
Alkaline minerals: Calcium, magnesium, potassium, and phosphorus in bioavailable forms.

Because wheatgrass is consumed in its raw, juiced form (or as a freeze-dried powder), its enzymes and heat-sensitive vitamins remain intact — something lost in cooked greens.

Gut Health and Ulcerative Colitis

The most clinically compelling evidence for wheatgrass concerns inflammatory bowel disease. A randomised, double-blind, placebo-controlled trial by Ben-Arye et al. (2002) gave 23 patients with active distal ulcerative colitis either 100 mL of wheatgrass juice or a matched placebo daily for one month [1]. The wheatgrass group showed statistically significant improvements in the overall Disease Activity Index, physician global assessment, and rectal bleeding compared to placebo. No serious adverse events were observed.

The probable mechanism involves chlorophyll's anti-inflammatory properties at the mucosal lining: it reduces pro-inflammatory cytokines and may support the repair of the epithelial barrier that is compromised in active colitis. Chlorophyll also has mild antimicrobial properties that may modulate gut bacteria toward a less inflammatory balance.

Cholesterol and Cardiovascular Support

A randomised controlled study by Kumar and Iyer (2017) assigned 59 hyperlipidaemic post-menopausal South Asian women to either 3.5 g of freeze-dried wheatgrass powder daily or no intervention for 10 weeks [4]. The wheatgrass group saw:

Total cholesterol reduced by 5.4%
LDL cholesterol reduced by 4.4%
Triglycerides reduced by 9.5%
Apolipoprotein B significantly lower at post-intervention (a marker of atherogenic particle count)

These effects are modest but meaningful over a short intervention period without dietary changes. The lipid-lowering mechanism is thought to involve both chlorophyll (which can bind to cholesterol in the gut and reduce its absorption) and the fibre and antioxidant compounds that reduce hepatic LDL production.

Blood Building and Iron Status

Wheatgrass has a longstanding folk reputation as a blood tonic, and some clinical evidence supports this in patients with haematological conditions. Marwaha et al. (2004) conducted a pilot study in children with beta-thalassaemia major — a condition requiring regular blood transfusions — and found that 100 mL of wheatgrass juice daily for one year reduced transfusion requirements in a meaningful proportion of participants [3]. The proposed mechanism involves both the iron content of wheatgrass and the chlorophyll's role in supporting haematopoiesis (red blood cell production).

For healthy individuals, the iron content of wheatgrass is relatively modest and wheatgrass is not a substitute for dietary iron sources. However, its combination of iron, folate, and B vitamins may offer cumulative support for those with borderline anaemia.

How to Use Wheatgrass

Fresh juice: 30–60 mL (1–2 oz) shots, best taken on an empty stomach in the morning. Strongly flavoured; many people chase it with citrus juice. Growing your own from trays is inexpensive.

Freeze-dried powder: 3–5 g mixed in water or smoothies. More convenient and better standardised than fresh juice. Look for products with no fillers.

Tablets: 500 mg–2 g capsules; lowest potency but most convenient.

Wheatgrass is completely gluten-free when harvested before jointing (the stem elongation phase). Anyone with coeliac disease should use a certified gluten-free product to be safe.

See our chlorophyll page for more on how chlorophyll works in the body, and our spirulina and chlorella page for comparison with other concentrated green superfoods.

Evidence Review

Ulcerative Colitis: Randomised Trial

Ben-Arye et al. (2002) conducted the highest-quality clinical trial of wheatgrass to date [1]. The double-blind, placebo-controlled design assigned 23 patients with active distal ulcerative colitis to 100 mL of wheatgrass juice or placebo for one month. The four-component Disease Activity Index (incorporating rectal bleeding diary records, stool frequency, sigmoidoscopic findings, and physician global assessment) was the primary endpoint.

Significant improvements were seen in the wheatgrass group for:

Overall Disease Activity Index score (p < 0.05)
Rectal bleeding (p < 0.05)
Physician global assessment (p < 0.05)

Sigmoidoscopic changes trended toward improvement but did not reach statistical significance, likely due to small sample size. The authors concluded that wheatgrass juice appeared safe and effective as a supplementary treatment for ulcerative colitis, while calling for larger trials to confirm the findings. The small sample remains the primary limitation of this work.

Cardiovascular Risk Markers: Randomised Controlled Study

Kumar and Iyer (2017) enrolled 59 hyperlipidaemic post-menopausal South Asian women, randomising 29 to daily wheatgrass supplementation (3.5 g freeze-dried powder) and 30 to control for 10 weeks [4]. The study was appropriately powered for lipid endpoints.

Results at 10 weeks in the intervention group compared to baseline-adjusted controls:

Total cholesterol: −5.4%
LDL cholesterol: −4.4%
Triglycerides: −9.5%
Apolipoprotein B: significantly reduced (p < 0.05)
HDL cholesterol: also reduced by 6% — an undesirable finding that the authors attributed to non-specific reductions in all lipoprotein fractions

The HDL reduction moderates enthusiasm for the cardiovascular findings. The intervention showed a net reduction in atherogenic particles (lower ApoB) which is a positive signal, but the simultaneous HDL reduction needs to be addressed in future studies using higher doses or longer durations.

Blood Transfusion Reduction in Thalassaemia

Marwaha et al. (2004) performed a pilot study in 16 children with transfusion-dependent beta-thalassaemia major [3]. Each patient served as their own control (comparing transfusion requirements in the intervention year versus the preceding year). Participants consumed approximately 100 mL of wheatgrass juice daily.

A proportion of participants showed a meaningful reduction in transfusion frequency over the intervention year. The pilot nature of the study, without a concurrent control group, limits causal interpretation. A subsequent larger study (Gupta et al., 2010; PMID 19205635) found more equivocal results — some patients responded well while others showed no benefit — suggesting individual variability in response, possibly linked to baseline folate and iron status.

Review of Evidence and Limitations

Bar-Sela et al. (2015) reviewed all human clinical evidence for wheatgrass across oncology, haematology, and gastroenterology settings [2]. Their overall assessment: the basic science data (antioxidant capacity, anti-inflammatory activity, chlorophyll content) is consistently positive, but the clinical trial base is small in both sample size and number of studies. The oncology applications — primarily as adjunct therapy during chemotherapy to reduce myelotoxicity — are the weakest evidentially, based on small case series and pilot data.

The review identified a common methodological issue: most trials used 100 mL of fresh wheatgrass juice, making dose standardisation difficult when comparing across studies using powder or tablets. Freeze-dried powder at approximately 3–5 g daily appears roughly equivalent but has not been directly compared to fresh juice in a head-to-head trial.

Strength of evidence summary:

Ulcerative colitis benefit: moderate (one small RCT, biologically plausible mechanism)
Cholesterol reduction: moderate (one RCT, consistent direction of effect)
Blood building/anaemia support: preliminary (pilot data, mixed results in follow-up)
Antioxidant activity: strong in vitro, moderate biological plausibility in vivo
Cancer adjunct therapy: insufficient clinical evidence

References

Wheat grass juice in the treatment of active distal ulcerative colitis: a randomized double-blind placebo-controlled trialBen-Arye E, Goldin E, Wengrower D, Stamper A, Kohn R, Berry E. Scandinavian Journal of Gastroenterology, 2002. PubMed 11989836 →
The Medical Use of Wheatgrass: Review of the Gap Between Basic and Clinical ApplicationsBar-Sela G, Cohen M, Ben-Arye E, Epelbaum R. Mini Reviews in Medicinal Chemistry, 2015. PubMed 26156538 →
Wheat grass juice reduces transfusion requirement in patients with thalassemia major: a pilot studyMarwaha RK, Bansal D, Kaur S, Trehan A. Indian Pediatrics, 2004. PubMed 15297687 →
Impact of Wheatgrass (Triticum aestivum L.) Supplementation on Atherogenic Lipoproteins and Menopausal Symptoms in Hyperlipidemic South Asian Women - A Randomized Controlled StudyKumar N, Iyer U. Journal of Dietary Supplements, 2017. PubMed 28121470 →