Heart disease in women has been linked to sharp changes in food supply suffered by their paternal grandmothers before they were 12 years old, according to new research which shows illness is heritable through the generations.
The findings, published in London by BMC Genetics today, emerged after a detailed investigation of harvest records during the 19th century in Overkalix in northern Sweden, where harsh conditions made harvests unreliable and help from southern parts of the country hard to get.
The years researchers chose were 1799-1800, 1876-1877 and 1880-1881, when good harvests were followed by bad ones; and 1812-1813 and 1821-1822, when years of scarcity were followed by years of plenty.
“If the paternal grandmother up to puberty lived through a sharp change in food supply from one year to next, her sons’ daughters had an excess risk for cardiovascular mortality,” the team said.
Risk of death
The food supply available during the early years for three of the four grandparents – maternal grandparents and paternal grandfather – had no effect on grandchildren's risk of death from heart disease.
“Only when paternal grandmothers’ food supply had these changes was it followed by high cardiovascular grandchild mortality, and then only by the sons’ daughters, not the sons’ sons,” the team said.
The health impact of a bad harvest on future generations is strongest but there were signs that going from starvation to plenty had negative impacts on female grandchildren, said the report. It said people who suffered famine as embryos often had strokes as adults.
