Study design
This 1-year intervention study had a randomized, controlled, cross-over design with an intervention and control period of both 5 months, separated by a wash-out period of 2 months. Randomization into 8 blocks was performed by an independent researcher using a computer-generated randomized block design with stratification for gender. During the intervention period participants daily consumed 50 g of whole, unsalted, unroasted almonds (Almond Board of California, California, United States). The nuts could be consumed at any time of the day, but all at once in one portion and not spread over the day. There were no instructions that the almonds should be consumed instead of any other item in the diet, allowing participants decide themselves as such mimicking the general guidelines to incorporate a handful of nuts in the daily diet. It was not allowed to consume any other nuts or nut products. Participants received a list of products that were not allowed at the start of the study and this limitation was emphasized during the follow-up visits. Participants were asked to note down their almond consumption in a diary, and to return the used and unused sachets to monitor compliance. During the control period participants were not allowed to eat almonds or any other nuts or nut products. All participants received instructions how to eat according the Dutch recommended dietary guidelines [A visit was planned at the start of both the intervention and control period for quantifying anthropometrics and blood pressure, and blood sampling. Next, two test days were scheduled at the end of each period, Study design