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How many calories do you need while breastfeeding?
Making breast milk uses about 500 calories a day in the first six months. Guidelines suggest eating about 330 calories a day more than your usual maintenance while exclusively breastfeeding a baby under 6 months (the rest comes from fat stored during pregnancy), and about 400 more from 6 to 12 months. For a 32-year-old woman of 70 kg (154 lb) and 165 cm at 6,000 steps a day, that's about 1,880 + 330 = 2,210 calories a day.
Calories while breastfeeding, by weight
| Weight | Usual | 0–6 months | 6–12 months |
|---|---|---|---|
| 55 kg 121 lb | 1,670 | 2,000 | 2,070 |
| 65 kg 143 lb | 1,810 | 2,140 | 2,210 |
| 75 kg 165 lb | 1,960 | 2,290 | 2,360 |
| 85 kg 187 lb | 2,100 | 2,430 | 2,500 |
| 95 kg 209 lb | 2,240 | 2,570 | 2,640 |
Why 330 and not 500?
A baby who is only breastfed drinks roughly 750–800 ml of milk a day, which holds about 500 calories. During pregnancy most women store some extra fat for this, and in the first months the body uses about 170 calories a day of it. That's why the guideline for the first six months is +330 rather than +500. From six months, as the baby starts solid food, milk volume drops but stored fat is usually used up, so the guideline is +400.
Partly breastfeeding or pumping
The addition follows the milk you make. If you combine breastfeeding with formula, or your baby feeds less often, you need less extra: somewhere between nothing and the full amount, in proportion to how much milk you produce. Pumping counts the same as feeding.
Losing weight while breastfeeding
Many women lose some weight naturally while breastfeeding. If you want to lose more, the usual advice is to wait until breastfeeding is well established, about 6–8 weeks after birth, and then lose gradually: no more than about 0.5 kg (1 lb) a week, through a modest cut and more walking rather than a strict diet. Large or sudden cuts can affect how you feel and, for some women, milk supply. Deficitly's goal planner isn't designed for breastfeeding, so check any plan with your midwife, health visitor or doctor.
Protein, fluids and nutrients
Protein needs rise while breastfeeding: the US recommended intake is 71 g a day, more than the 46 g for other adult women, and many women do better with more. Drink to thirst; many women find they need noticeably more than usual. Keep eating a varied diet, and ask about supplements such as vitamin D or iodine where you live. More on protein: how much protein you need.
Signs you may need to eat more
Constant tiredness beyond the usual broken nights, dizziness, losing weight quickly, or a drop in milk supply can all mean you're not eating enough. Talk to your midwife, health visitor, doctor or a lactation consultant, especially if your baby isn't gaining weight as expected.
Your usual maintenance
The base number is your normal TDEE: your resting burn plus daily life, steps and workouts. It falls slowly as your weight changes, so update it every few kilos. See how many calories a woman should eat and maintenance calories by daily steps.
Sources
- Institute of Medicine. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids. National Academies Press, 2005 (lactation: milk energy output and energy mobilized from tissue; protein 71 g a day).
- U.S. Department of Agriculture and U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2020–2025 (about 330 extra calories a day in the first 6 months and 400 in the second 6 months).