In this model bee decline is considered as a nutritional problem or a deficiency disease. In other words, due to inadequate or poor quality nutrition a bee colony becomes weakened and is therefore more susceptible to all sorts of parasites and diseases. This may be accompanied by insufficient strength to fly actively (reduced foraging distance) or insufficient ability to maintain the temperature in the hive. The deficiency can be alleviated by administering the limiting factor. The hypothesis is that the deficiency is iron, whereby various enzymes which depend on iron, notably those in the oxidative system, do not function sufficiently. 

Nutrients

During the Californian State Beekeepers Association convention in November 2012, every presentation emphasized the importance of bee nutrition. Interest in bee nutrition will increase further in the coming years.

By far the most research into bee nutrition has been conducted in Australia, particularly in the area of protein-rich nutrition. After some 10 years of research, from the early 1990s it took another 8 years before suitable products became available on the market.

The interest in protein-rich nutrition arose from the desire to quickly have sufficiently strong bee colonies in the spring for pollination. It has been established that administering protein-rich nutrition has not helped to prevent bee mortality. That makes sense, because protein mostly has a beneficial effect on brood growth.

No attention has been paid to the importance of minerals.

By administering additional iron the limiting factor in the bee nutrition can be eliminated and deficiency symptoms can be prevented.