Effect of Oat Consumption on Blood Pressure: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Effects of tocotrienol-enriched oat supplementation on metabolic profile, nutritional status and health-related quality of life among patients with metabolic syndrome

Background: Tocotrienol has garnered significant attention due to its potent antioxidant and anti-inflammatory effects in ameliorating cardiovascular-related comorbidities. The present study aimed to elucidate the effects of tocotrienol-enriched oat supplementation on individuals with metabolic syndrome (MetS). Method: This was a randomized, double-blind, placebo-controlled human clinical trial. Patients with MetS were randomized to the tocotrienol-enriched oat (TO), oat (O) or control (C) groups. Both TO and O groups were supplemented twice daily for 12 weeks, while group C did not receive any intervention. Changes in the metabolic profile of individuals were considered as the primary endpoint. The secondary endpoints included the morphological assessment of nutritional and anthropometric parameters and health-related quality of life. Other measurements included compliance and tolerability to the study regime. Results: The rate of MetS remission in the TO and O groups was approximately twice than that in the control group (37.0% vs. 18.5%). After 12 weeks, the TO group showed significant improvements in the fasting blood glucose (-4.5%), blood pressure (systolic: -4.2%; diastolic: -5.3%), high density lipoprotein-cholesterol (HDL-C) (+34.1%), and triglyceride (-7.1%) (p < 0.05) levels. Group TO demonstrated an increase in muscle mass (+0.301 kg, p < 0.05) and reduced body fat (-0.775%, p < 0.05). Both the TO and O groups showed improvements in the overall HR-QoL, and the visual analogue scale (VAS) score. Conclusion: Twelve weeks of tocotrienol-enriched oat supplementation improved surrogate endpoints associated with MetS. This complementary dietary management approach may be more effective at alleviating MetS symptoms than the pharmacological approach alone and could be a safe dietary strategy for secondary prevention.

Polysaccharides: The Sweet and Bitter Impacts on Cardiovascular Risk

Cardiovascular risk is a clinical factor that represents the probability of developing cardiovascular diseases (CVDs). This risk is shaped by non-modifiable and modifiable factors, including dietary patterns, which are the main lifestyle factor influencing CVD. Dietary polysaccharides, integral to nutrition, have varying effects on cardiovascular health depending on their type and source. They include starches, non-starch polysaccharides, and prebiotic fibers, categorized further into soluble and insoluble fibers. Soluble fibers, found in oats, legumes, and fruits, dissolve in water, forming gels that help lower serum cholesterol and modulate blood glucose levels. Insoluble fibers, present in whole grains and vegetables, aid in bowel regularity. The cardiovascular benefits of polysaccharides are linked to their ability to bind bile acids, reducing cholesterol levels, and the production of short-chain fatty acids by gut microbiota, which have anti-inflammatory properties. However, not all polysaccharides are beneficial; refined starches can lead to adverse metabolic effects, and chitosan to mixed effects on gut microbiota. This review examines the dualistic nature of polysaccharides, highlighting their beneficial roles in reducing cardiovascular risk factors and the potential adverse effects of specific types.

An encompassing review of meta-analyses and systematic reviews of the effect of oats on all-cause mortality, cardiovascular risk, diabetes risk, body weight/adiposity and gut health

The ability of oats to reduce blood cholesterol is well established but there is increasing evidence that its health benefits extend well beyond that. The purpose of this review was to critically evaluate the state of the science of oats in relation to all-cause mortality, cardiovascular and diabetes risk and the effects of oats on blood lipids, blood glucose, blood pressure, weight management and gut health from meta-analyses and systematic reviews. Limited epidemiological data indicated a possible beneficial effect of oats on all-cause mortality and incident diabetes when high versus low oat consumers were compared, but its effect on cardiovascular events was not adequately discerned. Observational data also showed an inverse association between oat intake and blood cholesterol, blood pressure, body weight and obesity variables in different populations. Randomized controlled oat intervention studies demonstrated a significant reduction in postprandial blood glucose in both diabetic and non-diabetic subjects, fasting blood glucose in diabetic subjects, blood pressure in prehypertensive individuals, and body weight and adiposity in overweight individuals. Increased fecal bulk was observed but clinical data for a potential gut barrier effect is lacking. The mechanism of action of each health effect was reviewed. While beta-glucan viscosity was once considered the only mode of action, it is evident that the fermentation products of beta-glucan and the associated gut microbial changes, as well as other components in oats (i.e., avenanthramides etc.) also play an important role.

Evidence on the use of alternative substances and therapies in hypertension

OBJECTIVE

Review of some of the best-known biological and non-biological complementary/alternative therapies/medicines (CAM) and their relationship with blood pressure (BP) and hypertension (HT).

SEARCH STRATEGY

Narrative review assessing a recent series of systematic reviews, meta-analyses, and clinical trials published in recent years, focusing on the effects of CAM on BP and HT.

SELECTION OF STUDIES

We searched EMBASE, MEDLINE, Cochrane Library and Google Scholar, obtaining a total of 4336 articles, finally limiting the search to 181 after applying filters.

SYNTHESIS OF RESULTS

Some studies on biological therapies show some usefulness in BP reduction with an adequate benefit-risk balance, although there is a scarcity of high-quality trials that support these results. Some mind-body therapies have shown hypothetical benefit; in contrast, others lack robust evidence.

CONCLUSIONS

Although some therapies present a reasonable risk-benefit ratio, they should in no case replace pharmacological treatment when indicated.

Polyphenols in Agricultural Grassland Crops and Their Health-Promoting Activities-A Review

Grassland crops are emerging reservoirs of undisturbed, natural antioxidants and phytochemicals, such as phenolic acids and flavonoids. The present review will focus on the most commonly cultivated crops, namely Lolium perenne L, Cichorium intybus L, Plantago lanceolata L. and Trifolium pratense L, which have been recognized for their polyphenolic composition. However, these crops are often undervalued and underutilized, yet have the means of potentially creating novel, value-added food and nutraceutical products. Previous studies relating to these crops have identified them as rich sources of caffeic acid, chlorogenic acid, daidzein, kaempferol, luteolin, and quercetin. The key to harnessing the hidden potential of these species is the recovery, identification, and characterization of the phytochemicals they contain. Considering the upsurge of research studies on alternative plant-based diets for the health of humans and the planet earth, there is a necessity to understand the phytochemical composition and the bioactivity that they possess. This review summarizes recovery methods of phytochemicals from the aforementioned grassland crops and their compositional and functional (antioxidant, anti-cancer, and anti-diabetic) characterization and discusses the potential for grassland crops as an abundant reservoir of health-promoting ingredients which can increase the nutritional composition within novel food innovations or within nutraceuticals.