Energy and protein requirements during lactation

Area of Science:

• Nutritional Science
• Human Lactation
• Maternal Health

Background:

• Breastfeeding is crucial for infant nutrition and maternal health.
• Understanding the precise energy and protein requirements during lactation is essential for supporting milk production and maternal well-being.
• Existing recommendations for increased caloric and protein intake during lactation require ongoing scientific validation.

Purpose of the Study:

• To determine the net energy requirements for exclusively breastfeeding women.
• To assess the impact of energy balance on lactation.
• To establish optimal protein intake recommendations during lactation.

Main Methods:

• Analysis of energy expenditure and metabolic adaptations during lactation.
• Evaluation of nitrogen balance studies in lactating women.
• Assessment of the relationship between energy reserves and lactation performance.

Main Results:

• Exclusive breastfeeding necessitates approximately 500 kcal/day, considering gradual weight loss.
• Limited evidence suggests energy-sparing adaptations in basal metabolic rate or thermogenesis during lactation.
• Reduced physical activity may occur postpartum, but adequate fat reserves mitigate negative energy balance effects on lactation.
• Recommended protein intake increase is around 20 g/day, accounting for milk's non-protein nitrogen content.
• Low protein intake may affect milk nitrogen composition rather than volume.

Conclusions:

• Lactating women require a modest caloric increase, with energy balance being a key factor.
• Protein requirements are higher than previously estimated to account for milk composition.
• Maternal nutritional status, particularly fat reserves, plays a role in maintaining lactation under varying energy intakes.