## Both famine and food surplus have consequences

The Dutch are said to be very meticulous people, so it's not surprising that their medical records correspond to this. In the past, when a Dutch woman became pregnant, doctors would record detailed information about the pregnancy, the birth, and many important details about the newborns. These records were destroyed after 15 years, but thanks to a lucky coincidence, one set of these - the records from the clinic of Wilhelmina Gasthuis - was kept in the attic and has survived to this day. These records are a rarity in that they were created in the very specific historical context of World War II. At that time, the Dutch were accustomed to a complete and balanced diet, as they had a high-quality agriculture. However, in 1944, realizing that it would soon be defeated by Allied forces, the German military leadership ordered railroads to be bombed, making it more difficult for the enemy to advance. The loss of a functioning railroad led to the food shipments blockage to some parts of the Netherlands, including Amsterdam, and famine spread through the region. The embargo lasted for 7 long months, until the liberation of the Netherlands in May 1945, at which point the energy intake for a person was less than 1,000 calories per day, and as low as 400 calories per day at the peak of the famine. The recommended number of calories for an adult is between 1,800 and 2,200 calories, depending on age and gender. The famine forced people to eat tulip bulbs and, combined with the harsh winter, mental strain, stress, and infectious diseases, led to a high mortality rate. Detailed medical records of this difficult period later provided scientists with very valuable information, especially since it lasted only a few months, affected a well-defined population, and all these people were malnourished at the same time. This combination of factors made it possible to study in detail how the given conditions affected the health of people born during this period. The result, compared to children born under normal conditions, the offspring of starving parents had twice the risk of developing cardiovascular diseases, obesity, diabetes, hypertension, and high cholesterol. In many cases, the inheritance of epigenetically modified gene expression was evident within the family line - from mothers to daughters and from fathers to sons.

The opposite of famine, is a food surplus, which occurs when the supply and availablilty of food is greater than the demand for it. Food surplus is linked to fertile years, and was more common in the days before the creation of a network of stores and supermarkets. Knowledge of these famine and surplus periods as well as the family situation was used in a 2014 study. The authors of this study analysed the causes of death of 239 people born in a small Swedish village in 1890, 1905, and 1920. They also obtained historical data on how the parents' families lived and their access to food during childhood. If the paternal grandfather (inheritance through the male line) had an excess of food during the pre-adolescent period, his grandchildren were four times more likely to die from diabetes-related complications than if he had a standard amount of food available. Surprisingly, the grandchildren had a lower risk of dying from heart disease if their father or paternal grandmother was starving during the pre-adolescent period. The explanation for the influence of diet is its effect on metabolic adaptation, which is written into sperm DNA and transmitted to offspring as an epigenetic modification.