This study investigates the health benefits of whole grain wheat on cardiovascular/ cardio-metabolic health, including glucose metabolism, by means of applying a mixed meal challenge. This study also investigates the health benefits of whole grain wheat (WGW) on liver- and adipose tissue health and evaluates the potential of do-it-yourself (DIY) devices in quantifying health effects in a nutritional intervention study.

The study is a randomized controlled, double blind, parallel trial. A 4-week run-in period with refined wheat (RW) products will be included prior to the intervention for all subjects. Thereafter, two different treatments will be evaluated e.g. a 12-week intervention with whole grain wheat (WGW) products (98g of WGW per day) and a 12-week control intervention with RW products. Two experimental visits will be planned before and two experimental visits will be planned after the 12-week intervention period. In the first experimental visit the investigators will determine liver fat and abdominal fat distribution by magnetic resonance spectroscopy (MRS) and magnetic resonance imaging (MRI). In the second experimental visit the investigators will comprehensively phenotype the participants which will include the response to a mixed meal challenge test.

The inclusion of subjects with mildly impaired cardio-metabolic risk profiles enables detection of improvements in health after WGW consumption. The investigators therefore aim to include 50 middle aged and overweight males or postmenopausal females (45-70yrs and BMI between 25-35 kg/m2) that have mildly elevated levels of cholesterol (cholesterol levels > 5 mmol/L). In case the inclusion of subjects with mildly elevated levels of total cholesterol is too difficult, normal levels of total cholesterol (< 5 mmol/L) can be accepted, but with a minimum total cholesterol level of 4.5 mmol/L.

Inclusion Criteria:

• Males or postmenopausal females (target 50: 50 for both genders) For females: menstrual cycle absent for more than 1 year
• Age 45-70yrs
• BMI between 25 and 35 kg/m2
• Signed informed consent
• Normal food habit of bread and cereal consumption

Exclusion Criteria:

• Not having a general practitioner
• Having a history of medical or surgical events that may significantly affect the study outcome
• Smoker
• Use of cholesterol lowering medication
• Mental status that is incompatible with the proper conduct of the study
• Aversion, intolerance to gluten, whole wheat or other items in the intervention products
• Alcohol consumption of > 21 glasses a week
• Abuse of drugs
• Recent use of antibiotics (<1 month prior to day 01 of the study)
• Reported weight loss or weight gain of > 5 kg in the month prior to pre-study screening
• Reported slimming or medically prescribed diet
• Reported vegan or macrobiotic life-style
• Not willing to give up blood donation during the study
• Personnel of Wageningen University, department of Human Nutrition, their partner and their first and second degree relatives
• Current participation in other research (with the exception of NQplus)
• Contraindication for MRI
• Having blood vessels that are too difficult for inserting a cannula