Pulses (beans, peas, and lentils) have been consumed for at least 10 000 years and are among the most extensively used foods in the world. A wide variety of pulses can be grown globally, making them important both economically as well as nutritionally. Pulses provide protein and fibre, as well as a significant source of vitamins and minerals, such as iron, zinc, folate, and magnesium, and consuming half a cup of beans or peas per day can enhance diet quality by increasing intakes of these nutrients. In addition, the phytochemicals, saponins, and tannins found in pulses possess antioxidant and anti-carcinogenic effects, indicating that pulses may have significant anti-cancer effects. Pulse consumption also improves serum lipid profiles and positively affects several other cardiovascular disease risk factors, such as blood pressure, platelet activity, and inflammation. Pulses are high in fibre and have a low glycemic index, making them particularly beneficial to people with diabetes by assisting in maintaining healthy blood glucose and insulin levels. Emerging research examining the effect of pulse components on HIV and consumption patterns with aging populations indicates that pulses may have further effects on health. In conclusion, including pulses in the diet is a healthy way to meet dietary recommendations and is associated with reduced risk of several chronic diseases. Long-term randomized controlled trials are needed to demonstrate the direct effects of pulses on these diseases.
In a randomized, double-blinded, controlled clinical trial, participants with peripheral arterial disease (75% hypertensive) consumed 30 g of milled flaxseed/d for 6 months. The flaxseed group exhibited significant reductions in systolic (−10 mm Hg) and diastolic (−7 mm Hg) blood pressure. Flaxseed contains the n3 fatty acid α-linolenic acid. Plasma α-linolenic acid increased with ingestion of flaxseed and was inversely associated with blood pressure. However, the antihypertensive mechanism was unclear. Oxylipins derived from polyunsaturated fatty acids regulate vascular tone. Therefore, the objective was to examine whether flaxseed consumption altered plasma oxylipins in a manner that influenced blood pressure. Plasma of FlaxPAD (Flaxseed for Peripheral Arterial Disease) participants underwent solid phase extraction and high-performance liquid chromatography–mass spectrometry/mass spectrometry analysis. The flaxseed group exhibited significant decreases in 8 plasma oxylipins versus control. Six of these (5,6-, 8,9-, 11,12-, 14,15-dihydroxyeicosatrienoic acid and 9,10- and 12,13-dihydroxyoctadecenoic acid) were products of soluble epoxide hydrolase, a pharmacological target for antihypertensive treatment. Patients exhibiting a decrease in total plasma soluble epoxide hydrolase–derived oxylipins, exhibited a significant decrease in systolic blood pressure (mean [95% confidence interval], −7.97 [−14.4 to −1.50] mm Hg) versus those who exhibited increased plasma soluble epoxide hydrolase–derived oxylipins (+3.17 [−4.78 to 11.13] mm Hg). These data suggest that a flaxseed bioactive may have decreased blood pressure via soluble epoxide hydrolase inhibition. Using a soluble epoxide hydrolase inhibitor screening assay, increasing concentrations of α-linolenic acid decreased soluble epoxide hydrolase activity ( P =0.0048; ρ=−0.94). In conclusion, α-linolenic acid in flaxseed may have inhibited soluble epoxide hydrolase, which altered oxylipin concentrations that contributed to the antihypertensive effects in patients with peripheral arterial disease. Clinical Trial Registration—: URL: http://www.clinicaltrials.gov . Unique identifier: NCT00781950
22 August 2011 in Journal of Agricultural and Food Chemistry