Table 2. Associations of development and growth with high protein formula intake in early life.
| Author, country (study) | Year | Study design | Age (mean ± SD or range) | Subject No. | Background nutrient intake | Comparison groups | Duration | Outcomes |
|---|---|---|---|---|---|---|---|---|
| Collell et al. [5], European-Childhood Obesity Program randomized trial | 2016 | RCT | 0–2 yrs | 47 | Breast feeding or formula | Breast feeding vs. LP formula1) vs. HP formula1) | 2 yrs | BMI was higher in HP formula group compared to LP formula and breast feeding group. |
| Cardiac function parameters were increased in HP formula group compared to LP formula group. | ||||||||
| Liotto et al. [6], Italy | 2018 | RCT | 5.3 ± 3.5 days | 50 | Breast feeding or formula | Breast feeding vs. LP formula2) vs. HP formula2) | 4 mon | No difference in weight gain among formula groups. |
| Fat-free mass increase in LP formula group was similar to that of breast feeding group. | ||||||||
| Oropeza-Ceja et al. [7], Mexico | 2018 | RCT | ≤ 40 days | 17 | Breast feeding or formula | Breast feeding vs. LP formula3) vs. MP formula3) vs. HP formula3) | 4 mon | Weight gain was greater in MP and HP formula compared to breast feeding. |
| Tang and Krebs [8], USA | 2014 | RCT | 5–6 mon (exclusively breastfed) | 18 | Exclusive breast feeding (no formula use) | Cereal group4) vs. Meat group4) (1–2 servings/day until 9–10 mon of age) | 5 mon | Weight-for-age z score and length-for-age z score in Meat group increased. |
| Weber et al. [9], European Childhood Obesity Project | 2014 | RCT | 5.3 ± 3.5 days | 24 | Breast feeding or formula | Breast feeding vs. HP formula5) vs. LP formula5) | 6 yrs | BMI increased in HP formula group. |
| Ziegler et al. [10], USA | 2015 | RCT | ≤ 3 mon | 82 | Breast feeding or formula at age 3 mon | Breast feeding vs. LP formula6) vs. HP formula6) | 9 mon | Weight gain from 3 to 6 mon was similar between LP and HP formula groups, but faster than breast feeding group. Odds ratios from 4 to 12 mon indicated fewer infants with weight > 85th percentile in LP formular group than in HP formular group. |
| *Complementary foods were allowed in small amounts from 4 to 6 mon and in unrestricted amounts after 6 mon |
RCT, randomized controlled trial; BMI, body mass index; LP, low protein; MP, middle protein; HP, high protein.
1)LP formula: 1.25–1.6 g/100 mL; HP formula: 2.05–3.2 g/100 mL.
2)LP formula: 1.2 g/100 mL; HP formula: 1.7 g/100 mL.
3)LP formula: 1 g protein/dL with bovine alpha-lactalbumin, 26% of total protein; MP formula: 1.3 g/dL with bovine lactalbumin; HP formula: 1.5 g/dL with standard infant formula, which is based on cow’s milk proteins, adjusted by the addition of whey protein concentrates to more closely resemble the whey protein-to-casein ratio of human milk of proximately 65:35.
4)Cereal group: fortified infant cereals as the first complementary food; meat group: commercially prepared pureed meats.
5)LP formula: 1.25 g/dL and 1.6 g/dL protein for follow-up; HP formula: 2.05 g/dL and 3.2 g/dL protein for follow-up.
6)LP formula: 1.61 g/100 kcal (modified bovine whey proteins with caseinoglycomacropeptide removed); HP formula: 2.15 g/100 kcal (unmodified bovine milk protein with a whey/casein ratio of 60/40).