Dieting While Breastfeeding – Does it affect your milk supply?

Dieting While Breastfeeding – Does it affect your milk supply?

Are you looking for tips to help get you back to your usual weight while breastfeeding? You are exactly where you need to be! For many mums, getting back to your pre-pregnancy weight after delivery is tough. There are so many things going on at this stage that paying attention to what you eat and trying to achieve a normal weight takes second place.

Taking care of a newborn, changing nappies, feeding your baby and adjusting to a new routine can be demanding, and it’s normal that you see yourself grabbing whatever you have available to eat without giving much thought to cooking a nourishing meal.

Nevertheless, it is important to return to a healthy weight and BMI (Body Mass Index) after delivery, especially if you put on too much weight during pregnancy or you were previously an obese woman. One reason is that post-partum weight retention is a risk factor for future obesity, heart disease, and type 2 diabetes.

So, returning to a normal weight while breastfeeding is so important, especially if you intend to get pregnant again in the future. This is because going into another pregnancy with excess weight can put you at risk for medical complications during the pregnancy or delivery, and returning to a healthy BMI later on is always easier said than done.

So, let’s cut to the chase and delve into the details. Read the helpful tips below to know how to achieve a healthy weight while breastfeeding.



Weight loss after pregnancy takes time, and usually it depends on how much weight you gained during those past 9 months. Although the biggest loss is often seen between three to six months after delivery, it is expected that a new mum returns to her usual weight over one to two years. So, you don’t need to rush and go for quick and maybe not so healthy solutions.

It might be the quickest way, but…

Caloric restriction might be a fast solution to get rid of those extra kilo’s, but this is not recommended for breastfeeding women. You should aim to eat according to your individual requirements, considering your age, nutritional status and physical activity, and avoid going on fad diets.

Energy needs for breastfeeding mums are considerably greater than those for women who are not breastfeeding. In simple words, the body requires extra energy to make milk. For example, the caloric requirements are about 500 additional Kcal per day beyond what is recommended for non-breastfeeding women, in order to help the body make the milk. After 6 months, when the baby usually starts eating solid foods, milk production decreases along with the mother’s energy requirements, so an additional 300-400 Kcal each day will fill caloric needs.

In any case, in this stage a women shouldn’t eat less than 1800 Kcal per day, as eating less than this amount can adversely affect breast milk volume, plus, a poor diet with a very low caloric supply might be lacking in essential nutrients and lead to changes in the nutrient composition of the human milk.

Breastmilk nutrients affected by maternal food consumption include Vitamin A; water-soluble vitamins such as Vitamin B-6, Vitamin B-12, and folate; iodine and selenium; as well as vitamin D and fatty acids whose importance in  the neurological and retina development of the baby has been discussed in previous blogs.

If you are breastfeeding, it’s best to wait for at least 2-3 months until lactation is well established, as trying to consciously lose weight before this time can have the adverse effects mentioned above. According to research, weight loss of approximately half a kilogram per week can be considered safe and does not affect the growth of the baby.

As we have said, how many calories you should eat is going to depend on many factors, so, this might be a good time to visit an Accredited Practicing Dietitian (APD) who can help you determine how many calories you need.


As we’ve mentioned earlier, breastfeeding is an excellent strategy to promote postpartum weight loss, due to the caloric costs required to make human milk, not to mention the metabolic or hormonal changes that are positive to weight loss. A study among U.S women showed that compared to women who did not breastfeed or breastfeed non-exclusively, exclusive breastfeeding for at least 3 months resulted in greater weight loss at 12 months after childbirth.

Also of note is that the positive weight loss benefits of breastfeeding won’t have the same effect on women who are moderately or morbidly obese, so these women will need to stick more to a meal plan and exercise.

During breastfeeding, hormones also play a key role, mostly with the rise of prolactin which is the hormone in charge of milk production. Prolactin also affects fat storage in your body and in some women the high levels of prolactin levels will prevent women from mobilizing fat stores and therefore affect weight loss, until breastfeeding is stopped. The levels of this hormone will vary from mum to mum, but are dependent on pre-existing maternal conditions, genetics, and stress.

Compounding this, when you’re breastfeeding, testosterone and estrogen levels are suppressed, and both of these are known for being fat burning.


You can eat most foods when breastfeeding, you just need to do your best to follow a balanced diet, just like when you were pregnant. You can obtain the extra energy and nutrients needed by eating slightly more of the same foods you already used to eat during pregnancy.

Can women gain weight during lactation? Yes, this occurs when they eat beyond those requirements for breast milk production.

A piece of advice: opt for nutrient-dense foods and steer clear of empty calories by cutting out refined carbs, sugary drinks, and junk food; eat more fruits, vegetables, wholegrains and protein foods, and on the counter keep healthy snacks to eat between meals, like plain yoghurt, cut vegetables, nuts and seeds.



If you’re on a post-partum weight loss plan, you need to consider physical activity needs along with diet. Exercise will not only help with weight management, but will also improve cardio respiratory fitness, plasma lipids, insulin response, preserve fat-free mass (ie. muscle) and help you feel good in general.

As with diet, exercise needs to be individualized and best to be discussed with an accredited exercise physiologist AFTER being cleared by a women’s health and continence physiotherapist to start exercise, but in general, moderate aerobic exercise of 45 minutes/day, 5 days/week can be a good fit for most women.

Lastly, remember to maintain an adequate liquid intake and get some rest. Poor sleep, stress and tiredness can negatively impact your weight loss efforts. As I said at the beginning, it might be difficult with all the new things going on after delivering your baby. But try to rest as much as you can, and don’t be afraid to ask for help when you need it. Don’t be afraid to ask your partner, friends and family to give you a hand from time to time to help you take care of the baby or with the house chores.

Be kind to your body…it’s gone through a massive marathon and you should be proud of the miracle it has helped you to achieve.

Be patient…your body is concentrating on giving vital nutrients to your baby, so it might take some time to restore your body shape back to what it once was!

Everybody is different… We all have different genes and hormonal profiles, living different lives of different activity levels. Embrace your uniqueness and try not to compare yourself to others during a beautiful but exhausting period in your life.

When you are ready, contact me to help you get back on track with your nutrition, ensure you are eating the right quantities of nutrients specific to breastfeeding, and to safely lose weight without losing your breastmilk supply.


Lovelady C. Balancing exercise and food intake with lactation to promote post-partum weight loss. Proc Nutr Soc. 2011 May;70(2):181-4. doi: 10.1017/S002966511100005X

Dewey KG. Effects of maternal caloric restriction and exercise during lactation. J Nutr. 1998 Feb;128(2 Suppl):386S-389S. doi: 10.1093/jn/128.2.386S

Mary Frances Picciano; Pregnancy and Lactation: Physiological Adjustments, Nutritional Requirements and the Role of Dietary Supplements, The Journal of Nutrition, Volume 133, Issue 6, 1 June 2003, Pages 1997S–2002S, https://doi.org/10.1093/jn/133.6.1997S

Jarlenski, M. P., Bennett, W. L., Bleich, S. N., Barry, C. L., & Stuart, E. A. (2014). Effects of breastfeeding on postpartum weight loss among U.S. women. Preventive Medicine, 69, 146–150. http://doi.org/10.1016/j.ypmed.2014.09.018

Jennifer L Baker, Michael Gamborg, Berit L Heitmann, Lauren Lissner, Thorkild IA Sørensen, Kathleen M Rasmussen; Breastfeeding reduces postpartum weight retention, The American Journal of Clinical Nutrition, Volume 88, Issue 6, 1 December 2008, Pages 1543 1551, https://doi.org/10.3945/ajcn.2008.26379

Lovelady CA, Garner KE, Moreno KL, Williams JP. The effect of weight loss in overweight, lactating women on the growth of their infants. N Engl J Med. 2000 Feb 17;342(7):449-53

Sheila M Innis. Impact of maternal diet on human milk composition and neurological development of infants, The American Journal of Clinical Nutrition, Volume 99, Issue 3, 1 March 2014, Pages 734S–741S, https://doi.org/10.3945/ajcn.113.072595

Amorim Adegboye AR, Linne YM. Diet or exercise, or both, for weight reduction in women after childbirth. Cochrane Database Syst Rev. 2013 Jul 23;(7):CD005627.  doi: 10.1002/14651858.CD005627.pub3

Lovelady CA. The impact of energy restriction and exercise in lactating women. Adv Exp Med Biol. 2004;554:115-20.

Mahan, L., Escott-Stump, S. and Raymond, J. (2011). Krause’s food & nutrition care process. Philadelphia, PA: Saunders.

University of Gothenburg. “Hormone Prolactin Reduces Fat Metabolism.” ScienceDaily. ScienceDaily, 5 April 2009. <www.sciencedaily.com/releases/2009/04/090402092859.htm>.





No Comments

Sorry, the comment form is closed at this time.