Previous - Next
It is likely that the recommendations for lactation will not need to be greatly altered from the 1985 values, but the presentation could be much improved.
As for pregnancy, we propose that any effects of possible changes in activity are expressed as PAL × BMR, and that any qualitative comments that might be made are cautious and given a low profile since there is no strong consensus as to what 'usually' happens in lactation. BMR can be predicted from the Schofield equations (1985) in the same way as for non-lactating women.
We propose that the recommendation should have categories for full breastfeeders and partial breastfeeders after 3 months post partum.
With regard to weight loss and the consequent subsidizing of the costs of lactation, in our opinion fat loss is not a programmed component of lactation, as has been assumed in the past. Other behavioural and environmental factors play an important modulating role. The current assumption of approx 500 g/month seems to be a reasonable reflection of the usual pattern in well-nourished, unstressed women, but should probably not be assumed for other groups, particularly when pregnancy fat gain has been minimal. The 1985 recommendations give precedence to the assumption that lactation will be subsidised, and then state that the full cost should be met if this is not the case. We propose that this logic should be reversed and that the full costs should be clearly stated.
The overall recommendations are summarised in Table 12. If more global average figures are required we recommend the following: 2650 kJ/day (635 kcal/day) for 0-6 months with no fat loss or 2000 kJ/day (480 kcal/day) allowing for fat loss; and 2200 kJ/day (525 kcal/day) beyond 6 months for full-breastfeeders or 1200 kJ/day (285 kcal/day) for partial breastfeeders.
Table 12 Suggested figures for energy requirements during lactationa
|
Energy requirementc (kJ/day) | |||
|
Period (month) |
Milk volumeb (g/d) |
Full costs |
Allowing for fat lossd |
|
All women | |||
|
0-1 |
680 |
2380 |
1730 |
|
1-2 |
780 |
2730 |
2080 |
|
2-3 |
820 |
2870 |
2220 |
|
Full breast-feeders | |||
|
3-6 |
820 |
2870 |
2220 |
|
6-12 |
650 |
2275 |
2275 |
|
12-24 |
600 |
2100 |
2100 |
|
Partial breast-feeders | |||
|
3-6 |
410 |
1430 |
780 |
|
6-12 |
325 |
1140 |
1140 |
|
12-24 |
300 |
1050 |
1050 |
a As the text emphasises, the values are increments to be added to the maternal requirements calculated using PAL × BMR (PAL may be slightly reduced if there is evidence of lower activity during lactation in the population being considered).
b Derived from studies in Sweden (Sadurskis et al, 1988), England (Paul et al, 1988), USA (Heinig et al, 1993a,b) and the WHO Collaborative Study on Breast-Feeding (WHO, 1985). Values include a +4% adjustment to allow for insensible water losses from the baby during test-weighing.
c Assumes energy density of breast-milk to be 2.80 kJ/g and dietary milk energy conversion efficiency of 80%.
d Assumed to be approx. 500g/month up to 6 months post-partum and nothing thereafter.
Acknowledgements - The preparation of this paper was greatly assisted by written submissions from LH Allen, KG Dewey, JVGA Durnin, E Forsum, JC King, C Panter-Brick, B Schürch and Y Schutz.