I am breastfeeding my baby and I want to lose weight. Is a low carbohydrate diet safe for a breastfeeding mother?

Many women are anxious to get back in shape after childbirth, but we must remember that pregnancy weight wasn’t gained overnight, and won’t disappear quickly, either. It is wise for mothers to wait until two months postpartum to purposely lose weight, as the mother’s body needs time to recover from childbirth and establish a good milk supply. Many mothers find that by following a sensible diet they are able to lose weight steadily while breastfeeding. Anyone who wants to start a weight loss diet should consult with their physician to rule out any health problems that would contraindicate the diet. If a breastfeeding mother is interested in any type of weight loss diet, there are several factors she should consider.

Nutritional balance-- A breastfeeding mother should receive adequate and balanced nutrition, for her breastfed baby’s sake, and the sake of her own health. Otherwise, she risks depleting her body’s nutritional stores. A malnourished mother may have inadequate levels of vitamins A, D, B6 and B12 in her milk, and may risk decreased milk supply.

Hunger-- Inadequate caloric intake results in feeling weak, tired, and drained. When a mother feels this way, taking care of a baby is very difficult, and these very real feelings can result in lowered milk supply and inhibited milk ejection (letdown) reflex. The Subcommittee on Nutrition during Lactation advises breastfeeding mothers to take in 1500-1800 calories per day.

Rate of weight loss-- Gradual weight loss has not been found to affect either the mother’s milk supply or the baby’s health. However, there are documented concerns when a breastfeeding mother loses weight rapidly, defined as more than a pound (.45 kg) per week. Toxins, such as environmental contaminants PCBs and pesticides, are stored in body fat. When a breastfeeding mother loses weight rapidly, these toxins may be released into her bloodstream, and the toxin levels in her milk may increase. Rapid weight loss has also been linked to a decrease in milk supply.

There are a number of low carbohydrate diet plans, and all are based on the theory that by limiting carbohydrates and eating adequate amounts of protein, the dieter will be freed of the cravings and hunger that are typical of other weight loss plans. The diets differ in the degree and manner of carbohydrate restriction. Some encourage dieters check for ketosis by using special urine test strips. Ketosis occurs when the body burns fat instead of glucose for energy, and is marked by the presence of ketones in the urine. Ketones are any of three toxic, acidic chemicals (acetone, acetoacetate, and beta-hydroxybutyrate) that build up in the bloodstream.

Many people who follow low-carbohydrate diets do lose weight more rapidly than is wise for a breastfeeding mother. It would be possible to modify a plan to include more carbohydrates in the form of fruits and starchy vegetables, which would slow the weight loss.

There are some concerns that it is not safe for a breastfeeding mother to be in ketosis, whether she is following a low carbohydrate diet or burning fat in some other manner. It is unknown if the ketones that are excreted into the blood and urine are also present in the milk, and if so what levels would pose a danger to the breastfeeding infant. The Atkins Center website’s FAQ section recommends that pregnant and breastfeeding women adjust their carbohydrate intake to the maintenance level, which is considerably higher than the weight-loss level.

Another possible concern is that these diets are too high in protein, but a breastfeeding mother secretes 6 to 11 grams of protein in her milk every day, and growing babies need that protein, which is the body’s basic building material. Protein, unlike some other nutrients, can not be stored in the mother’s body. The US Department of Agriculture recommends that a lactating woman consume 65 grams of protein per day. Many women who follow the Brewer Pregnancy diet, which recommends 80-100 grams of protein per day, continue to follow that diet during lactation. Another concern might be the amount of fat in these diets, but lactating women do need a certain amount of dietary fat. According to Eat Well, Lose Weight While Breastfeeding, the recommended daily requirement of the fats and oils food group is 7 servings per day, with a minimum of 5. Though low carbohydrate diets do prescribe what some may consider large amounts of animal protein, it can certainly be lean protein.

Some people who follow a low carbohydrate diet also use artificial sweeteners, which many breastfeeding mothers choose to avoid. It is possible to follow a low-carbohydrate diet without using artificial sweeteners.

No “diet” is a one size fits all proposition, and that is especially true for breastfeeding mothers. With research and some care regarding balanced nutrition and rate of weight loss, a breastfeeding mother might choose to follow certain elements of the low- carbohydrate diet, and leave the rest behind.

Our FAQs present information from La Leche League International on topics of interest to parents of breastfed children. Not all of the information may be pertinent to your family's lifestyle. This information is general in nature and not intended to be advice, medical or otherwise. If you have a serious breastfeeding problem or concern, you are strongly encouraged to talk directly to a La Leche League Leader. Please consult health care professionals on any medical issue, as La Leche League Leaders are not medical practitioners.

Last updated Monday, September 11, 2006 by njb.

Page last edited Sun Oct 14 09:29:18 UTC 2007.