Sweeteners in Breastmilk
by Anne Eglash MD, IBCLC, FABM
The number of natural and artificial sweeteners is overwhelming. Avoiding them used to be as easy as avoiding diet sodas and diabetic candy. Now, they are added to several products that are considered ‘healthy’ such as sports drinks, low carb snacks, and low sugar dark chocolate bars. There have been concerns that they may alter metabolism and increase the risk of obesity and insulin resistance. So, if sweeteners can have these effects on the consumer, what about the infant who is consuming these products via breastmilk? In this week’s article, ‘How Sweet It Is: Sweeteners in Breast Milk’ Dr. Phillip Anderson summarizes our current knowledge regarding the transmission of sweeteners into breastmilk. We have some data on several sweeteners, but none so far on stevia and monkfruit.
Fructose in the maternal diet has caught the attention of researchers because intake of high fructose sweeteners such as high fructose corn syrup, honey, and agave syrup in the maternal diet increase fructose levels in breastmilk.
- Aspartame does not appear in breastmilk because it is broken down into 2 amino acids in the gut.
- Sorbitol in the maternal diet has been shown to cause diarrhea in the infant.
- Breastmilk fructose levels are associated with infant body weight and body composition at 6 months of age.
- There is evidence that increased sweetness of breastmilk increases an infant’s risk of increased sugar intake and obesity.
- The sweeteners acesulfame, saccharin, and sucralose are found in breastmilk after maternal ingestion, at variable levels considered safe.
See the Answer
The obesity epidemic in the United States and other countries has increased the use of artificial sweeteners. However, their effectiveness in reducing blood glucose and in promoting long-term weight loss as well as their safety in preventing obesity in children have been questioned because studies are inconsistent in their designs and findings. This column reviews the available information on the use of various sweeteners in nursing mothers. Additional references on specific sweeteners can be found in the corresponding LactMed records.
All of the sweeteners listed in this article can be found in the National Library of Medicine LactMed database.
The sugar alcohols, including sorbitol, mannitol and xylitol, can cause diarrhea when consumed, but so far we don’t have evidence that they are detectable in breastmilk. Aspartame levels are not present in breastmilk because it is broken down in the maternal gut into aspartic acid and phenylalanine, which are amino acids.
There is preliminary research evidence that a maternal diet high in fructose may increase body weight and fat mass in breastfed infants. When mothers consume foods or beverages high in fructose, the level of fructose rises in breastmilk. This is not true for glucose, because maternal insulin rapidly normalizes the maternal glucose level after glucose ingestion. Insulin does not moderate the fructose level like it does for glucose.
And increasing sweetness of breastmilk via artificial or natural sweeteners in the maternal diet might predispose to later obesity. This may be partially mediated by an alteration in the gut microbiome by the sweeteners.
Perhaps it is time to increase awareness of maternal sweetener intake, especially regarding fructose sweeteners, in order to lower the risk of childhood obesity.