Chapter 2: Provide nutrition in lactation

Nutrition during lactation is a critical area of focus for Nutrition and Dietetics professionals in Kenya. This chapter explores the unique nutritional demands faced by lactating mothers and the implications for infant health and development. Understanding these needs enables dietitians and nutritionists to provide tailored advice that supports both maternal well-being and optimal infant growth. In Kenya, where maternal and child nutrition challenges persist, such expertise is essential for improving health outcomes at community and clinical levels.

2.1 Nutritional needs in lactation

Lactation is the period in which a mother makes milk for her baby. It places a heavy load on her body, because her food must now support both her own recovery and the milk that is the infant's only source of nutrition in the first six months. This topic describes how the body produces milk, why the mother's nutrition matters, and how a dietitian assesses a breastfeeding mother's needs, including the energy, nutrient and fluid requirements that differ from pregnancy.

2.1.1 Introduction to nutrition in lactation

Nutrition in lactation means the food and nutrient intake a mother needs to produce enough milk of good quality while keeping her own health. The quantity of milk depends mostly on how often and how effectively the baby feeds. The mother's nutrition affects how much of her own stores are drawn on, and the content of some nutrients in the milk. A dietitian supporting a breastfeeding mother therefore looks at her diet, her stores, her workload and her feeding pattern together.

Breastfeeding is promoted for the first six months of exclusive feeding and continued with other foods for two years or beyond. Mothers may face food insecurity, infections, long working hours and limited variety in meals, all of which can strain their reserves.

Physiological changes during lactation

After delivery, hormones start milk production. Prolactin drives milk synthesis in the breast, and oxytocin causes the milk to flow when the baby suckles. The more often milk is removed, the more is made. The body spends extra energy on synthesis, and when food intake is too low it draws on fat stores laid down in pregnancy and, for some nutrients, on the mother's own tissues. Appetite and thirst rise as a result.

Breast milk composition and its nutritional value

Breast milk contains water, lactose, fat, protein, vitamins and minerals, together with antibodies and other protective factors. The first milk, colostrum, is thick, rich in antibodies and low in volume. Over the next days to weeks it changes into transitional and then mature milk. A well-nourished mother produces roughly 750 to 800 mL of milk a day on average in the first six months.

Some milk components stay fairly stable even when the mother's intake is low, such as protein, lactose, calcium, iron, zinc and folate. For these, her stores supply the difference. Others change with her diet: the fatty acid pattern, iodine, vitamin A, several B vitamins and vitamin D. This is why the mother's intake of those nutrients matters directly for the baby.

Impact of maternal nutrition on lactation outcomes

Inadequate intake can lower the mother's stores and, for the nutrients that follow her diet, lower their content in her milk. A mother who is deficient in iodine or vitamin A may pass lower amounts to the baby. Maternal depletion over repeated closely spaced pregnancies and lactations adds to the risk. Support early in lactation protects the mother and the infant.

2.1.2 Importance of nutrition in lactation

Good nutrition in lactation protects two people at once. For the infant, it supports the nutrients in the milk. For the mother, it helps recovery after birth, protects her stores and gives her the strength to care for the baby.

Support for infant growth and development

For the first six months, breast milk supplies the infant with all the energy and fluid needed, and most nutrients. The mother's diet affects the nutrient content of her milk in the cases described above. A mother who eats a varied diet and is well hydrated supports her infant's brain development, immunity and growth.

Maintenance of maternal health

Lactation raises the need for energy, protein, fluids and several vitamins and minerals. If intake is low, the mother may lose weight too fast, become tired and anaemic, and lose bone mineral for a time. Eating enough keeps her energy up for the demands of night feeds and household work.

Prevention of nutritional deficiencies

Mothers are at risk of low iron, vitamin D, zinc, iodine and vitamin A. A dietitian encourages varied foods and, where needed, recommends supplements according to national guidelines and the clinician's advice. Nutrition counselling at postnatal and child welfare visits is a convenient point to check and advise.

Enhancement of breastfeeding duration and quality

A mother who eats and drinks enough is less tired and more able to breastfeed often, which supports milk supply. Hunger, thirst and exhaustion make breastfeeding harder. Counselling on practical ways to fit meals and drinks around feeds keeps her going.

Socioeconomic and cultural relevance

Cultural beliefs about postpartum foods, who prepares meals and whether the mother returns to work or farm duties soon after birth all affect her intake. Some families encourage nourishing foods such as porridge and soup, while others restrict some foods. A dietitian respects traditions that help and discusses gently those that restrict useful foods.

2.1.3 Assessment of nutritional needs in lactation

Assessment in lactation uses the same four sources as in pregnancy: body measurements, laboratory tests, clinical examination and diet history. The difference is that the dietitian also considers the mother's breastfeeding pattern, her return to work, the stage of lactation and the infant's growth as a sign of whether feeding is going well.

Socioeconomic and environmental factors in assessment

The woman's circumstances shape her intake and are part of the assessment. A dietitian asks about:

• Food security: whether there are enough meals and whether variety changes with the season.
• Workload: whether she must farm, trade or work away from the baby, and when she can eat and drink.
• Support at home: who prepares meals, who minds the baby and who decides household food spending.
• Water and sanitation: whether clean water is available for drinking and for hand washing.
• Health factors: HIV status and treatment, chronic illness, use of family planning and alcohol use.
• Cultural practices: postpartum food customs and restrictions.

2.1.3.1 Anthropometry

Anthropometry in lactation shows whether the mother has recovered from pregnancy and whether her weight is coming down gradually. A dietitian measures weight, height, MUAC and BMI using the same method as in antenatal care. A cut-off such as 23 cm is used in several national guidelines for pregnant and breastfeeding women and differs between guidelines, so the facility's own cut-off is followed.

After birth, most women keep some of the weight gained in pregnancy. Gradual loss while breastfeeding is generally safe when the mother keeps eating regular, varied meals. Rapid loss from strict dieting is not advised, because it can reduce energy and nutrient intake.

Worked example: a woman weighed 61 kg before pregnancy and is 1.65 m tall. At the six-week postnatal visit she weighs 67.5 kg. Her pre-pregnancy BMI was 61 ÷ (1.65 × 1.65) = 61 ÷ 2.7225 = 22.41, rounded to 22.4 kg/m². Her BMI now is 67.5 ÷ 2.7225 = 24.79, rounded to 24.8 kg/m². The weight retained is 67.5 − 61 = 6.5 kg. Returning to 61 kg will take many weeks. The dietitian explains that there is no need to rush, that the aim is steady, gentle loss with regular good meals, and that her weight is checked again at each postnatal visit.

The baby's weight is a linked indicator: poor infant weight gain prompts a review of the mother's intake and of feeding technique, as covered in the chapters on infant nutrition.

2.1.3.2 Biochemical assessments

Biochemical tests show whether the mother's stores and function are adequate. They are requested through the clinician. Tests used in lactation include:

• Haemoglobin: a breastfeeding woman who is not pregnant is considered anaemic by WHO if haemoglobin is below 12.0 g/dL. The bands are mild (11.0 to 11.9 g/dL), moderate (8.0 to 10.9 g/dL) and severe (below 8.0 g/dL).
• Serum ferritin: low values show depleted iron stores, even when haemoglobin has not yet fallen.
• Blood glucose: women who had gestational diabetes are advised to have a glucose test after delivery, as directed by the clinician.
• Vitamin D, B12 and folate levels: used where deficiency is suspected, for example in a woman who eats no animal-source foods.
• Urinary iodine: used in surveys to judge whether lactating women as a group have enough iodine. A median of 100 µg/L or more in a group is considered adequate. It is not used for one woman.

Single-use lancets and test strips are used for each woman and sharps are disposed of safely.

2.1.3.3 Clinical monitoring

Clinical monitoring looks for signs of poor nutrition and for postnatal problems that affect eating. WHO advises postnatal contact within the first 24 hours, around day 3, between days 7 and 14, and at six weeks. The dietitian works with the midwife at these contacts.

Things to check include:

• Pallor: pale palms and inner eyelids may indicate anaemia after blood loss at delivery.
• Wound healing: slow healing of a caesarean or perineal wound may point to poor protein, vitamin C or zinc intake, or to infection that is referred.
• Blood pressure: raised pressure after delivery is referred to the clinician.
• Fever, severe pain, heavy bleeding: referred at once.
• Mood: persistent sadness, anxiety or loss of interest are referred to the clinician or counsellor.
• Infant signs: fewer than six wet nappies a day after the first week, or poor weight gain, suggest that the baby is not getting enough milk and need a review of feeding.

A dietitian does not treat infections or wounds. Findings go to the clinician and are noted in the nutrition record.

2.1.3.4 Dietary assessments

Dietary assessment finds out what the mother eats and drinks and how this compares with her needs. The methods are the 24-hour recall, the food frequency questionnaire, the food diary and the diet history, as used in antenatal care. Breastfeeding mothers often have little time, so short forms are practical. The dietitian also asks how often the baby feeds, whether feeding is exclusive and whether the mother skips meals when busy or at night. Reported intake is compared with reference values from WHO, FAO and national guidelines.

Worked example: a mother's recall shows tea with milk and bread at breakfast, ugali and beans at lunch, and rice with kale and a small fish at supper. The food groups are grains, dairy, pulses, dark green leafy vegetables and fish, so five groups are present. There is no fruit or vitamin A-rich vegetable, so the dietitian suggests orange-fleshed sweet potato, pumpkin or mango.

The nutrient sections that follow describe the needs against which intake is judged.

2.1.3.4.1 Energy requirements

Making milk costs energy. Milk carries about 65 to 70 kcal per 100 mL, so around 780 mL a day contains roughly 500 kcal, and the process of making it is not fully efficient. Part of the cost is met from fat stored during pregnancy, and the rest must come from food.

A joint FAO, WHO and UNU consultation estimates an additional 505 kcal a day for the first six months for a well-nourished mother who gained a healthy amount in pregnancy. The Institute of Medicine uses a smaller increase of 330 kcal a day for the first six months and 400 kcal a day for the second six months, which allows for fat stores being used.

Worked example: a mother's energy need before pregnancy was about 2,100 kcal a day. With the FAO, WHO and UNU figure, the planning figure for the first six months is 2,100 + 505 = 2,605 kcal. With the Institute of Medicine figure, it is 2,100 + 330 = 2,430 kcal. The 2,100 kcal is hypothetical, and the dietitian chooses the reference used in the facility. The advice is to eat to appetite, with extra meals or snacks.

A mother who gained little weight in pregnancy has fewer stores and needs more from food than one who gained well.

2.1.3.4.2 Macronutrients

Macronutrients are protein, carbohydrate and fat, together with fibre. In lactation, protein needs rise because milk contains protein, and the mother needs it for recovery. The additional amount is about 19 g a day in the first six months and about 12.5 g a day after that. Beans, cowpeas, eggs, fish, milk, groundnuts, meat and poultry are good sources.

Carbohydrate gives energy for milk making. The reference intake is 210 g a day. Staples such as ugali, rice, sweet potato, cassava and banana provide it. Wholegrain forms add fibre and B vitamins. Fat provides energy and the fats that build the baby's brain. The fat in the mother's milk reflects the types she eats, so fish, groundnuts, avocado and vegetable oils are helpful, while fried snacks and fat-heavy processed foods are limited. Fibre of about 29 g a day from wholegrains, pulses, vegetables and fruit helps to prevent constipation after birth.

2.1.3.4.3 Iron

Iron needs in lactation are lower than in pregnancy, at about 9 mg a day for an adult woman (Institute of Medicine), because menstruation is usually absent while a mother breastfeeds exclusively. Iron in breast milk is low and does not rise with the mother's intake. The reason to look at iron is the mother's own health: blood lost at delivery, low stores before pregnancy and early return of periods can leave her anaemic.

A dietitian checks haemoglobin at the postnatal visits, asks about heavy bleeding and the foods eaten, and encourages liver, meat, small dried fish with bones, beans and dark green leafy vegetables, with vitamin C-rich fruit. The woman continues iron and folic acid after birth for the period set by the national guideline, particularly if she had anaemia. Tea and coffee are kept away from meals. Her iron needs rise again when her periods return.

2.1.3.4.4 Iodine

An exclusively breastfed baby gets iodine only from milk, and the milk's iodine content follows the mother's intake. WHO recommends 250 µg a day for breastfeeding women. Low iodine in milk can affect the baby's brain development.

Iodised salt is the main practical source, along with fish, milk and eggs. Salt is stored in a covered container away from heat and damp, and is added late in cooking. Large doses of iodine from seaweed supplements are avoided, because too much iodine can disturb the thyroid. A dietitian asks about salt use and whether the household's salt is iodised.

2.1.3.4.5 Vitamin D

Vitamin D supports calcium absorption and the baby's bone growth. The reference intake in lactation is 15 µg (600 IU) a day (Institute of Medicine). Breast milk is usually low in vitamin D unless the mother's own level is good, so the baby's vitamin D comes mainly from sunlight and, where advised, a supplement given to the infant, as decided by the clinician.

Mothers can make vitamin D in the skin through regular short exposure of the face and arms to sunlight, depending on skin tone, clothing and time spent outdoors. Foods that help include fatty fish, egg yolk and fortified products. Women who stay indoors for long periods after birth, which some customs encourage, may be at risk, so the dietitian discusses outdoor time with the family.

2.1.3.4.6 Folic Acid

Folate stays in breast milk even when the mother's stores are low, which means her own stores can be drawn down. The reference intake in lactation is 500 µg of dietary folate equivalents a day (Institute of Medicine). Folate matters for the mother's blood and for any further pregnancy: a woman who conceives soon after birth with low folate has a higher risk of a baby with a neural tube defect.

Good sources are dark green leafy vegetables, beans, cowpeas, liver, oranges and fortified flours. Because folate is lost with long cooking, vegetables are cooked briefly. A mother who might conceive again soon is advised about family planning and folic acid supplements.

2.1.3.4.7 Zinc

Zinc is needed for the mother's healing, immunity and appetite and for milk synthesis. The reference intake is 12 mg a day in lactation (Institute of Medicine). Zinc content in milk falls gradually over the months of lactation regardless of the mother's intake, so the mother's own zinc stores are what the dietitian protects.

Sources are meat, fish, eggs, milk, beans, groundnuts and pumpkin seeds. In diets that rely on unrefined maize, sorghum or millet, phytates block zinc absorption, and soaking, fermenting and germinating the grains helps. Supplements are given only on the clinician's advice, because high doses disturb copper balance.

2.1.3.4.8 Micronutrients influencing milk quality

Some micronutrients in breast milk rise or fall with the mother's intake. These need particular attention.

A mother who eats no animal-source foods needs a vitamin B12 supplement, as advised by the clinician. High-dose preformed vitamin A is not given without clinical advice, and WHO does not recommend routine vitamin A supplementation for all mothers after delivery.

2.1.3.4.9 Increased Fluid Needs

Milk is about 87% water, so a breastfeeding mother loses fluid daily and needs to replace it. The Institute of Medicine sets the adequate intake of total water at 3.8 litres a day for lactating women, of which about 3.1 litres comes from drinks and the rest from food.

A useful guide is thirst, together with pale yellow urine. Some mothers feel thirsty during feeds, so a cup of water placed within reach before each feed helps. Suitable fluids are clean boiled or treated water, uji, soup and milk. Sugary drinks and heavy tea or coffee are kept limited. Drinking far more than thirst does not raise milk supply. A mother with dark urine, headache, dry lips or constipation needs more fluid.

Chapter Summary

This chapter explored the nutritional needs during lactation, emphasizing the critical role proper nutrition plays in supporting both the mother and the infant. It detailed various methods for assessing nutritional status in lactating mothers, including anthropometric measurements, biochemical tests, clinical monitoring, and dietary assessments. The discussion then shifted to breastfeeding-related complications, identifying common issues such as sore nipples, breast engorgement, mastitis, nipple vasospasm, and challenges posed by inverted or flat nipples. An introduction to nutrition intervention outlined the essential steps in developing a nutrition plan and described different intervention types such as supplementation, diet planning, deworming, and education. The process of carrying out nutrition interventions was examined with a focus on implementation steps and necessary tools and resources. Finally, the chapter covered the monitoring and evaluation of nutrition interventions, highlighting the importance of systematic tracking through anthropometry, biochemical and dietary assessments, clinical observations, and specific indicators of success, while also acknowledging the challenges faced in this process.