The history of infant feeding is a classic display of how opinion varies like the swing of a pendulum. The longer you are involved with this topic, the more you realize this fact. Over the years, seat-of-the-pants feelings alternated between starting solids as early as one month to giving nothing but breast milk until one year of age. Each generation of parents was told something different.
Until recently, scientific observation played a very small role in the establishing of feeding concepts. It was at the whim of the health professional who made the noise. Fortunately, we now have some facts that might guide us in the formulation of feeding policies. If we look at the basic issues, it becomes clear that we should not focus on solid feedings, but the feeding of any foreign protein, liquid or solid. Too often parents staunchly oppose starting vegetables and fruits but fill the child needlessly with cow or soy protein in liquid form without concern. In other words, a breast-fed baby is given cow protein formula supplements even though the mother could easily use her stored breast milk. This is usually done because it seems easier. On the other hand, if insufficient breast milk is present, a foreign protein formula is used because there is no alternative. As you can see, I feel breast milk feeding is desirable because it keeps the infant free of ANY foreign protein challenge that can lead to the development of specific food allergies.
How long should one avoid exposure to these proteins? Research by pediatric gastroenterologists (intestinal disease specialists) and allergists have yielded some very pertinent information. From birth to approximately six months of age the lining of the intestinal tract is like a microscopic sieve. The “pores” allow large, whole protein particles to pass from the contents of the intestinal tract, through the porous lining, into the bloodstream. These protein molecules stimulate the immune system to produce reactive substances (antibodies) against them. Ultimately, these antibodies react with the same type protein to provoke an allergic reaction. At approximately age six months these micro pores seal and the whole protein has a more difficult time making the same trip from inside the intestine to the immune cells in the bloodstream.
From this information, we can see how it might make sense to delay the feeding of multiple food and drink until the infant reaches six months of age. Anything we can do to decrease the incidence of food allergy will be very important to the future well being of the child. Food allergy is a gigantic problem in older children and adults. Unfortunately, it frequently goes unrecognized and patients suffer needlessly.
Understanding how the infant intestine changes with age it becomes clear that we should minimize the number of foreign proteins to which our little ones are challenged before the age of six months. Furthermore, it is well recognized that infants thrive on breast milk or a single formula during the first six months without the introduction of solids.
Will the starting of solid feedings at six months definitely reduce food allergies later on in life? No one can say, but theoretically it seems logical. If in years to come we find the incidence of food allergy remains the same despite this feeding concept, we will have lost nothing. On the other hand, if we find a great reduction in the number of food allergy patients, the gain in general health, school attendance, work-force production and the reduction of medical costs, it will have been a great benefit not only to the individual but also to society in general.