Published in the physical edition of the Japan Pharmacology and Treatment journal, the study found that kale powder could reduce systolic blood pressure (SBP) but not diastolic blood pressure (DBP) in hypertensive subjects.
The randomised, double-blind study recruited 92 people aged 20 to 64 with SBP between 130 to 159mmHg and DBP levels between 85 to 99mmHg.
Subjects were divided equally into the treatment or control group. The treatment group was given 14g of kale powder dissolved in 100 to 150mL of water daily for 12 weeks.
The kale powder was provided by Q’sai, a Japanese manufacturer of health foods and skincare products.
Subjects’ SBP and DBP were recorded before the assessment. At weeks four, eight and 12, the change in blood pressure values (ΔBP) were recorded.
At week eight, the study reported a significant difference in ΔSBP between both groups (p=0.04). The change in SBP was -9.7±8.9 mmHg in the treatment group and -3.8±7.9 mmHg in the control group.
At week 12, ΔSBP was -10.8±10.7 mmHg for the treatment group and -4.6±9.2 mmHg in the control group, although this difference was not significant (p=0.07).
The results in ΔDBP was found to be not significant.
In Japan, hypertension affects about 43 million people in Japan, and is the main cause of cardiovascular and kidney diseases.
Q’sai said in mild cases of hypertension, the recommended treatment was lifestyle modifications to the diet and exercise. In severe cases, lifestyle changes and medications were recommended.
The study concluded that kale intake could be a recommended method in reducing blood pressure in individuals with high BP, although further studies can be conducted in the future.
In Australia, researchers are also studying the effects of kale consumption on its blood pressure lowering effects. The study which is currently recruiting, will investigate if the different types of vegetables such as cruciferous (broccoli, cabbage, cauliflower, kale) or commonly consumed vegetables (potatoes, carrots, pumpkin) would affect the vascular and metabolic function in people with mildly elevated blood pressure.
Q’sai retails its kale food series, ‘Aojiru’ which has since been renamed to ‘The Kale’ in January this year. In Japan, kale is commonly consumed as a green juice instead of its vegetable form.
The company started manufacturing its ‘Aojiru’ range in 1982 starting with frozen kale.
Besides health foods, Q’sai is also involved in cosmetics since 2009. Yoshimi Fukunaga, from the firm’s public relations told us the company launched a new skincare brand Skinkalede in October 2019, which incorporates kale as an ingredient.
Source: Japan Pharmacology and Treatment
“Effect of Intake of Kale on Blood Pressure in Subjects with Elevated Blood Pressures－A Randomized, Double-blind, Placebo-controlled, Parallel-group study”