End of Summer Report

Alexandrea Papadelias

The Effect of Diet and Nutrition on the Chemical Composition of Breast Milk Samples

The research question of focus is what is the effect of diet and nutrition on the chemical composition of breast milk samples. Currently, I have extended my research deeper on the free fatty acid content of breast milk, as well as vitamin content, and the methodology used in the lab. It has been indicated by previous experimentation that environmental factors influence the composition of breast milk, and this impact is larger than previously believed. The composition of human milk is very complex and therefore, is affected by so many variables. The mother diet has a recorded effect on the proportions of fatty acids in breast milk samples. Both the amount and type of certain nutrients affect the fatty acid content of milk samples. Similarly, the intake of vitamins plays a role in the levels present in human milk. One big factor of this research is where the body sources the components to produce breast milk.

For the case of vitamin content in human milk, it is sourced from the mother’s intake and her vitamin stores. However, this relationship varies depending on the type of vitamin. If the mother’s intake of certain vitamins is low, often the body will just source the vitamins from the reserves of those vitamins in the mother’s body. It can be generalized that a diet that consists of chronically low levels of certain vitamins will be reflected in the vitamin contents of human milk. Usually, a diet that exceeds the recommended amount of whatever component does not affect the composition of human milk. However, this is untrue for vitamins B6 and D. Vitamin D is particularly interesting because it relies partly on exposure to sunlight. If the mother is not exposed to regular sunlight and her intake is low, the infant breastfeeding will be at risk for vitamin D deficiency. Race can also play a role in vitamin D composition. Research showed that races of a darker complexion had lower levels of certain forms of vitamin D due to a decrease in the skin’s production of vitamin D. A study published in 1967, concluded that black mothers have lower levels of vitamin D2, D3, and 25-hydroxyvitamin D3 than white mothers. Vitamin D2 correlated to ranges that are normally consumed.

If a mother is a vegetarian, this can affect the fatty acid content of her milk as well as the vitamin composition. Studies showed that vegetarian mother’s milk contained five times as much C18:2 fatty acids during the early stages of lactation when the body is sourcing it from the diet intake. In the case of vitamin B12, breastfed infants are at an elevated risk of deficiency, even if the mother does not show signs of deficiency.

The fatty acid content of human milk is interesting to look at because it can be affected by where it is sourced from in the body or the types of fat consumed by the mother, as opposed to the amount.  It is approximated that, when a mother has balanced energy, 30% of fatty acids found in human milk are derived directly from the diet. Fatty acids and monoglycerides with antiviral properties are generated by the hydrolysis of fats.

The methodology previously employed was qualitative research and the goal was to discover research on the environmental effects on breast milk. Moving forward, as the fall semester begins, this research will develop into experimental research. This research will be continued by analyzing breast milk samples from the Philippines to determine the content of free fatty acids, vitamins, minerals, and polycyclic aromatic hydrocarbons. This will be done by preparing and treating samples by transesterification and will require the use of instruments such as gas chromatography, atomic absorption spectrometry, and high-performance liquid chromatography. One typical use of gas chromatography is to separate the different components of a mixture. By pretreating the samples with transesterification and using gas chromatography, we can determine fatty acids common in samples, and those that are more unique. Specifically, another student and I will be focusing on analyzing samples using gas chromatography for free fatty acids, HPLC for vitamin content, and AAS for minerals present.

So far, I have accomplished a foundational understanding of the environmental factors affecting breast milk, which will be used to further analyze this topic in the lab. Moreover, the findings will then be curated into a presentation during the upcoming fall semester.

This experience has been very fulfilling and rewarding so far. The information I have gathered will be extremely useful in my continuing pursuit of this insightful research. I am so grateful for the opportunity and look forward to the future. Ultimately, we hope to contribute new perspectives on how environmental factors affect free fatty acid profiles and other nutrient contents of breast milk.


Blog 2: The Effect of Diet and Nutrition on the Chemical Composition of Breast Milk Samples

Former experimentation indicates that environmental factors do influence the composition of breast milk, and have a larger impact than previously believed. Because the composition of human milk is so unique and is affected by so many variables, many sources of error exist in the collection of data. However, it has been studied that certain nutrients and non-nutrient constituents of milk can decrease with a chronically lower maternal intake of these nutrients. This then can result negatively on the infant. Likewise, a chronically low intake of certain components can have a neutral result on the breast milk if the components are then sourced from the mother’s own internal reserves.

Maternal dietary intake can impact the proportions of different fatty acids present in milk samples. The intake of lipids affects milk composition by altering the type of fatty acid present. Lipid composition of milk demonstrates the unique way human milk components are sourced in the body. Fatty acids can be derived from plasma transported from the intestine/fat deposits or can be synthesized from glucose. Those synthesized within the mammary gland have a chain length of 16 carbons or less, whereas, the chain length of fatty acids derived from the maternal diet tend to be longer. During lactation, lipoprotein lipase activity in the mammary gland increases which hydrolyzes triglycerides, freeing the fatty acids for transport and further use within the cell.

Rather than the amount of fat intake by the mother affecting the amount of fat within the milk, we see that the type of fat consumed influences the fatty acid composition of the milk. An experiment in Great Britain compared the breast milk of four vegetarian women to that of four non-vegetarians. The results suggested that the milk from the vegetarian mothers contained five times as much C18:2 fatty acids within the early stages of lactation. As time progressed, however, the milk of both groups began to contain more fatty acids synthesized from the mammary gland. The type of diet of the mother seems to impact the type and source of the fatty acid used in the composition of breast milk. By using stable isotope methodology, the results of a study showing that diet composition affects milk fat synthesis were confirmed. The study further showed that when the mother’s energy levels are balanced, the “fatty acids derived directly from the diet account for approximately 30% of the fatty acid found in the milk.”

Moving forward, more research on factors that affect fatty acid content and how the type of fatty acid that is present due to environmental factor affects the human milk sample will be done. Also, the research can be compared to the group’s collected research in the lab. This research poses a challenge just because there are so many varying factors that can affect the composition of breast milk. Through this research so far, I have learned a lot about the complexity of human milk composition and the many bodily processes that contribute to its formation.

Blog 1: The Effect of Diet and Nutrition on the Chemical Composition of Breast Milk Samples

The title of my undergraduate research project with Dr. Mojica is: “The Effect of Diet and Nutrition on the Chemical Composition of Breast Milk Samples.”

Breast milk contains the fundamental nutrition that a baby needs in its early development. The composition of breast milk usually contains fats, proteins, carbohydrates, and minerals. However, this composition can be influenced by various environmental factors, such as diet, duration of the pregnancy, maternal parity, and the stage of the lactation. This research will shed more light on the effect of diet and nutrition on the chemical composition of breast milk samples.

Through this research, we hope to contribute scientific information on the effect of environmental factors on breast milk composition. Since similar reported studies have varying results depending on the location, we hope to contribute new perspectives with the factors that affect free fatty acid profiles of breast milk.

The research is going to be carried out by compiling literature results and comparing them to tested results. The free fatty acid profiles of breast milk will be the focus in order to study the effect of diet and nutrition. This literature review will support previous scientific research lead by Dr. Mojica.