Health Benefits of Whole Grain Oats in Population at Risk of Cardio-metabolic Disease

Hypocholesterolaemic and Prebiotic Effects of a Whole-grain Oat-based Breakfast Cereal in a Cardio-metabolic 'at Risk' Population

Intake of whole grain cereals has been associated with reducing the risk of hyperlipidaemia and heart disease, however the mechanisms by which oats or oat fractions exert this effect is not totally clear. Furthermore, several large epidemiological studies and a number of recent meta-analyses of nutritional interventions have reported a positive association between increased whole grain intake and reduced risk of developing a range of chronic diseases. Recognising the important role of the gut microbiota in metabolism and metabolic disease risk, we examined the impact of whole grain oats on the human gut microbiota and cardio-metabolic risk factors. The main aims of this human study is to determine the effectiveness of a low GI whole grain oats breakfast cereal compared to a high GI, refined breakfast cereal to beneficially modulate gut microbiota and its metabolic output, plasma lipids, gut satiety hormones and inflammation markers in an at risk of cardio-metabolic disease population

Volunteers had to consume wholegrain cereals oats (WGO)(45g/day) for six weeks followed by a four week wash out period.

Volunteers had to consume non wholegrain cereals (NWG)(45g/day) for six weeks followed by a four week wash out period.

Volunteers had to consume wholegrain cereals oats (WGO)(45g/day) for six weeks followed by a four week wash out period

Volunteers had to consume non wholegrain cereals (NWG)(45g/day) for six weeks followed by a four week wash out period.

Changes in faecal bacteria populations upon consumption of the test and control cereals . Faecal samples were collected and analysed at 0, 42, 56, 112, 140 days

High-performance liquid chromatography (HPLC) was performed to determine faecal SCFA concentration. Faecal samples were collected and analysed at 0, 42, 56, 112, 140 days

Fasted plasma samples were analysed for determination of triacylglycerol (TAG), total cholesterol (TC), HDL-cholesterol, LDL-cholesterol. Blood plasma samples were collected and analysed at 0, 42, 56, 112, 140 days

Fasted plasma samples were analysed for determination of insulin resistance, PYY and GLP-1. Blood plasma samples were collected and analysed at 0, 42, 56, 112, 140 days

Fasted plasma samples were analysed for determination of IL-6, TNF-a while saliva samples were analysed for sIgA and faecal samples for calprotectin. Blood plasma samples and saliva and faecal samples were collected and analysed at 0, 42, 56, 112, 140

4-day diet diaries were collected analysed, to determine the macro and micronutrient content of the participant's diets during each intervention arm. Diet diaries were collected at were collected and analysed at 42 and 112 days.

Inclusion Criteria: Men and Women (age range 23-64 y) BMI of 18-30kg/m2 Fasting glucose concentration >5.5 but <7.5mmol/L Total cholesterol >5.2 but <7.8mmol/L Exclusion Criteria: medical history of heart disease, diabetes mellitus, cancer, pancreatitis or renal disease use of lipid lowering drugs, systemic corticosteroids or drugs for regulating hemostasis exposure to any investigational agent <42 d before the study presence of gastrointestinal disorder or use of a drug likely to alter gastrointestinal motility or nutrient absorption history of substance misuse or alcoholism current pregnancy, planned pregnancy, or given birth in the past 12 months antibiotic treatment 6 weeks previous to study start date allergy or intolerance to intervention breakfast cereals components smoking

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Connolly ML, Tzounis X, Tuohy KM, Lovegrove JA. Hypocholesterolemic and Prebiotic Effects of a Whole-Grain Oat-Based Granola Breakfast Cereal in a Cardio-Metabolic "At Risk" Population. Front Microbiol. 2016 Nov 7;7:1675. doi: 10.3389/fmicb.2016.01675. eCollection 2016.