 This study is a randomised, cross-over, dietary intervention trial. Healthy adult 18 y participants from the community will be recruited by means of an advertisement leaflet and word of mouth. Eligible participants will be enrolled in the study. We will thank those subjects who have expressed an interest about the study but are not suitable to participate and we will explain to them why they need to be excluded. Those who are eligible and willing to participate will be asked to undertake two different experimental diets, for seven days each: 