To the Editor:
The article "Nutritional Issues for Infants and Toddlers" by Dr. Aldous, which appeared in the February 1999 issue, is thorough and well written.1 However, I must take issue with the following statement:
Because of its low caloric density and high protein and electrolyte load, low-fat milk is not recommended by the AAP until age 2 years, (p. 101)
The reference given is the fourth edition of the Pediatrie Nutrition Handbook. However, when the book is consulted, the following statement can be found on pages 132 and 133:
Nonfat and low-fat milks are not recommended for use during the first 2 years of life because of the lower calorie density compared with whole-fat products.
That is certainly true. However, the recommendation has nothing to do with solute load. I think the author misinterpreted Table 4.1 (on page 50 of the Pediatrie Nutrition Handbook), "Renal Solute Load of Various Infant Food Types." That table lists foods by mOsm/100 kcal (ie, solute load per calorie, not solute load per volume). The solute loads per volume of whole milk, low-fat milk, and skim milk are almost identical. (The utility of this table is questionable because it is not referred to anywhere in the book.)
Similarly, the protein loads in whole milk, low-fat milk, and skim milk are almost identical, yet Dr. Aldous' article implies there is a significant and important difference between them. There is not. The recommendation for whole milk is based on the fact that we want toddlers to have a relatively high-fat diet. I take no issue with that. However, it is interesting how sacred the creed of whole milk has become and how little real research there is on the subject. It is possible to have a healthy high-fat diet without whole milk.
1. Aldous MB. Nutritional issues for infants and toddlers. Pediatr Ann. 1999;28:101-105.
Mike Dubik, MD
Naval Medical Center
Dr. Aldotis' response:
I thank Dr. Dubik for the correction. The American Academy of Pediatrics (AAP) discourages low-fat milk before age 2 because of its low caloric density.1 Fresh cow's milk contains two to three times more protein, sodium, potassium, and chloride per volume than human milk, which is one of the reasons why the AAP does not recommend its use (regardless of fat content) before 1 year of age.1
It is true that the protein and electrolyte contents per volume) are similar for whole and low-fat milk. However, volume intake in infants and food intake in young children varies considerably to preserve a relatively constant daily caloric intake.2"4 Thus, infants, and probably toddlers, fed lower fat milk ingest greater volumes and therefore more protein and electrolytes than those fed whole milk. The significance of this higher protein and electrolyte intake is unclear except in infants, who should not be fed fresh cow's milk anyway.
1. Kleinman RE, ed. Pediatrie Nutrition Handbook, 4th ed. Elk Grove Village, IL: American Academy of Pediatrics; 1998:40, 132, 631.
2. Fomon SJ, Filer LJ, Thomas LN, Rogers RR, Proksch AM. Relationship between formula concentration and rate of growth of normal infants. / NM ir, 1969;98:241-254.
3. Fomon SJ, Filer LJ, Thomas LN, Anderson TA, Nelson SE. Influence of formula concentration on caloric intake and growth in infants. Acta Paediatr Scand. 1975;64:172-181.
4. Birch LL, Johnson SL, Andresen G, Peters JC, Schulte MC. The variability of young children's intake. N EnglJMed. 1991^24:232-235.