TABLE 3.
RNIs for infants and lactating women: United Kingdom1
| Milk | Infant RNI3 | Lactation, units/d | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Nutrient | Concentration, unit/L | Intake from milk (0–6 mo),2 units/d | 0–6 mo | 7–12 mo | Increment over NPNL | EAR | RNI | Data | Comments |
| Thiamin, mg | 0.16 | 0.14 | 0.3 | 0.3 | 0 | 0.3 | 0.4 | Milk concentration from 5-center study in United Kingdom (66). | Infant RNI also considers report of higher concentration by 6 wk (67); n = 5; United Kingdom |
| Riboflavin, mg | 0.31 | 0.26 | 0.4 | 0.4 | +0.5 | 1.4 | 1.6 | Milk concentration from 5-center study in United Kingdom (66). Infant RNI is amount that restored normal EGRAC values in Gambia. In lactation, covers amount in milk + metabolic cost of its secretion. | Details of samples and populations not cited or available |
| Niacin, mg | 2.7 | 2.3 | 3 | 4 (7–9 mo), 5 (10–12 mo) | +2.3 | 12.3 | 15 | No reference for milk value. | — |
| Vitamin B-6, μg/g protein | 8 | 6.8 | 8 | 10–13 | 0 | 13 | 15 | Milk value from Department of Health and Social Security (68). | Original source of data not available. Units differ from those of other organizations |
| Vitamin B-12, μg | 0.2–1.0 | 0.3 | 0.3 | 0.4 | +0.5 | 1.75 | 2.0 | For infants, intake to normalize MMA (9); n = 19, of whom 13 were strict vegetarians. For lactation, 0.5 μg/d should ensure adequate supply to milk. | Source is 1988 textbook (69) |
| Folate, μg | 40 | 34 | 50 | 50 | +60 | 210 | 260 | Milk concentration based on Swedish study (70); n = 91. In lactation, to replace 40 μg/d in milk + incomplete absorption and utilization from diet. | Swedish women with adequate folate status. Samples from <1 mo (n = 47), 1 to <6 mo (n = 13), and 6–12 mo (n = 31). |
| Vitamin C, mg | 30–80 | 25–68 | 25 | 25 | +30 | 55 | 70 | Source of milk concentration not stated; 25 mg/d RNI to prevent scurvy (would be equivalent to 32 mg/L). For lactation, to maintain maternal stores and circulating concentration in upper 50% of physiologic range. | — |
| Vitamin A, μg RAE | — | — | 350 | 350 | +350 | 750 | 950 | FAO/WHO recommendation for infants in 1988 (71) | — |
| Vitamin D, IU | — | — | 340 | 280 | 10 | 0 | 10 | Milk vitamin D concentrations not used. In lactation to prevent observed decline in maternal 25(OH)D. | No RNI for NPNL adults |
| Vitamin E, mg TE | 3.2 | 2.7 | ≥0.4 mg TE/g PUFAs | — | N/A | N/A | N/A | Infant data from single study (23); n = 24. No DRVs for adults because requirement depends on PUFA intake. | Mature milk (12 d to 5 mo); from milk bank in Sweden collected after infant fed |
| Vitamin K, μg | 1–10 | <1 | 10 | 10 | N/A | N/A | N/A | RNI based on milk value of 10 μg/L to prevent hemorrhagic disease of newborn (26); n = 9. Data judged inadequate to set adult DRVs. | Well-nourished German mothers, at 1, 3, 5, 8, 15, 22, 29, and 36 d of lactation. Complete breast expression. Median: 1.2 μg/L at 8–36 d. Higher in colostrum (median: 2.7 μg/L) and hind- vs. foremilk; 10 μg/L likely only possible with maternal supplementation |
| Iron, mg | 0.4 (6–8 wk), 0.29 (17–22 wk) | 0.25–0.34 | 1.7 (0–3 mo), 2.3 (4–6 mo) | 4.2 | 0 | 11.4 | 14.8 | Milk concentration from Finnish study (72). For infants, assumes 10% bioavailability from formula. Needs for lactation offset by amenorrhea. | 1–3 mo of lactation. Original data not available |
| Copper, mg | 0.22 | 0.19 | 0.3 | 0.3 | +0.3 | N/A | 1.5 | Milk concentration is average of 1–6 mo; n = 10 (73). For lactation, to replace copper excreted in milk, assuming 50% absorption. | Middle class, apparently well-nourished women in United States sampled monthly to 18 mo or weaning. No EAR for adults |
| Zinc, mg | 2.5 (1–4 mo), 1.1 (5–12 mo) | 2.13 (1–4 mo), 0.94 (5–12 mo) | 4.0 | 5.0 | +6.0 (0–4 mo), +2.5 (>4 mo) | 11.5 (0.4 mo), 8 (>4 mo) | 13 (0–4 mo), 9.5 (>4 mo) | Source of milk concentration not stated. Infant RNI based on factorial method. Assumes 30% absorption from adult diet. | — |
| Calcium, mg | 350 | 298 | 525 | 525 | +550 | 1075 | 1250 | No source for milk concentration. For infants, 160 mg/d retention, 40% absorption from formula. In lactation, 300 mg/d secreted in milk, and 40% absorption from diet. | — |
| Magnesium, mg | 28 | 25 | 55 (0–3 mo), 60 (4–6 mo) | 75 (7–9 mo), 80 (9–12 mo) | +50 | 250 | 320 | Milk concentration from Department of Health and Social Security guidelines (68). For lactation, assumes absorption from diet is 50%. | Original source not available |
| Iodine, μg | ∼60 (estimated from DRI) | 50 | 50 (0–3 mo), 60 (4–6 mo) | 60 | 0 | N/A | 140 | 30–40 μg/L in milk produces no signs of deficiency in infant (45); n = 37. No increment for lactation. | United States, during period of high iodide intake. No EAR for adults |
| Selenium, μg | 12 | 5–13 | 10 (0–3), 13 (4–6 mo) | 10 | +15 | N/A | 75 | Milk concentrations of 8–30 μg/L in United Kingdom (74). In lactation, assumes 60% absorption. | Original data from report on selenium in British food. Data unavailable. No EAR for adults |
1Data are from DRVs for food energy and nutrients for the United Kingdom (65). DRV, Dietary Reference Value; EAR, Estimated Average Requirement; EGRAC, Erythrocyte Glutathione Reductase Activity Coefficient; MMA, methylmalonic acid; NPNL, nonpregnant, nonlactating; RNI, recommended nutrient intake; TE, alpha-tocopherol equivalent; 25(OH)D, 25-hydroxyvitamin D.
2Calculated by assuming 850 mL milk/d consumed from ages 0–6 mo.
3DRVs are intended for formula-fed infants; panel saw no value in setting them for breastfed infants.