It’s no new news that you should eat well while you’re pregnant. But what a lot of people don’t realize is the importance of eating well BEFORE you fall pregnant – during the preconception period. I try to teach my patients the importance of a healthy preconception care diet for both mother and father for at least 4 months before they are going to try to conceive.
Considering how hard it is to eat a healthy, nutrient dense diet when you have morning sickness, it makes the 4 month preconception care period all the more important (although I don’t think there’s a period of life when you shouldn’t eat well).
The reason for this time frame is because sperm can take 116 days to generate and during this time they are easily susceptible to damage. Similarly, the egg is vulnerable during maturation for around 100 days leading up to ovulation.
The damage that I’m referring to is of the genes of the sperm and the egg. If the genes of either are altered, then the foetus is more likely to develop a stronger tendency to genetic conditions such as autism, schizophrenia, genetic cancers, physical malformations and can increase general ill-health.
The thing about DNA is that some genes can be turned on and off like a light switch. Our environment i.e. the food that we eat and the chemicals that we’re exposed to control these switches – this concept is referred to as epigenetics. Methylation is another player in this whole process – it is a chemical ‘tagging’ process which aids in activating certain proteins in our body and silencing some genes. This process is dependent on healthy levels of certain B vitamins – deficiencies in these vitamins can lead to an increase in DNA damage and when methylation isn’t working properly it can also cause problems in adults as well, such as heart disease, mood disorders and more.
While the research in this field is still in its infancy (haha, get it?) the research that we do have available is certainly interesting.
Most of the research that has been done in this field has been on mice. Any information that we get from animal research can never be fully extrapolated into recommendations for humans because mice and human metabolisms are worlds apart. It is a starting point however.
The human research that has been done has mostly been on the mother, and until recently it has mostly been during pregnancy. I believe the diet and supplements for the preconception period are just as important for the father however, and while there is some research in this area it is minimal in comparison.
The most well known study is that of the agouti mice. A selection of mice that were genetically identical were exposed to certain chemicals or dietary changes during their pregnancies that triggered gene changes in their pups, which was displayed as the production of the agouti protein, which turned their hair yellow. This same protein also prevented the mice from being able to feel full, and they developed obesity and were more prone to cancer and diabetes. Some of the mice did not express this gene and so remained of normal weight and brown and some mice developed a mottled yellow-brown colour, only having partial gene expression. They were all genetically identical, however their gene expression was different.
Diet during pregnancy
Another study found that mice fed a high fat diet during pregnancy produced mice with altered metabolisms and also had brain changes which resulted in an impaired ability to feel when they were full. The third trimester and breastfeeding period were most important in this aspect. Something to note is that the ‘high fat’ diet that these mice are fed is actually a concoction of hydrogenated vegetable fats, mixed with sugar. This is a far cry from what is commonly understood to be ‘fats’, as the production of these fats turns them into rather toxic substances. Your everyday, whole-food sort of fat found in avocadoes, nuts and seeds, fish and meat are not going to cause the same issue but hydrogenated fat found in fast food and processed food are going to cause problems.
A human study compared the amount of weight a mother gained in each of her pregnancies, and found that if the mother gained too much weight during a pregnancy the child was more likely to develop obesity, even more than 10 years later, compared to when the mother kept to a healthy weight range during her pregnancy. There are a lot of factors which could influence this, but a possible mechanism is that methylation can be reduced in those who are overweight.
This study looked at a group of women in Gambia and analyzed their diet and nutrient status during the preconception period. There were two groups of women analyzed – one who had conceived at the peak of the rainy season, and one who had conceived at the peak of the dry season. The women who had conceived at the peak of the rainy season had greater nutrient levels, notably the B vitamins essential for healthy methylation, and their babies were found to have greater amounts of DNA methylation. The study also found a correlation between the mothers BMI and methylation levels.
This study doesn’t mean that we have to wait until it rains to try to conceive, but rather it highlights the importance of eating nutrient dense food.
The moral of the story? If you’re planning to conceive, are pregnant or breastfeeding aim to eat a variety of fresh, whole, seasonal , nutrient dense foods and avoid exposure to environmental chemicals as much as possible.