Data on commonly consumed portion weights of individual foods were obtained from MAFF (1993)
and Gregory et al. (1990) and converted to amounts that should be consumed on a weekly
basis, with some adjustments such as the removal of alcohol and miscellaneous foods. In
addition, the weight of fluids, milk and fruit juice, were halved before being added to the
weights of the rest of the foods in the milk and dairy, and fruit and vegetable groups
respectively. The reason for this was that these fluids contain a high proportion of water and
are used in large quantities in the diet. The weight of all foods was then totalled. The
relative proportions (segment size) of food to be consumed from each food group were then
calculated from these weights. As a percentage of the total for this, the five food groups
were comprised as follows: bread, other cereals and potatoes (34%), fruit and vegetables
(33%), meat, fish and alternatives (15%), milk and dairy foods (12%) and fatty and sugary
foods (7%) (Gatenby et al., 1995). The 101% total is due to rounding up.
The BOGH model showed the balance of foods we should try to eat for a healthy diet.
Whilst aiming to achieve this balance every day could be a practical approach, it was not
considered necessary to achieve it at every meal and could instead be achieved over the
period of perhaps a week. The key message was that it is the balance of foods in the diet as
a whole that is important to achieve a healthy diet
Other than recommending consumption of at least 5 portions of fruit and vegetables per day
and 2 portions of fish, one of which should be oily (in the accompanying text), no guidance 9
was given with the BOGH on numbers of servings. Instead, the emphasis was on proportion
(size of segments) given that everyone has different needs that are difficult to quantify