Deep in the belly of our cells, chromosomes carrying genetic information unspool and unfurl, stretching out, offering up the blueprints of our bodies. Embedded in our DNA are detailed instructions for when it’s time for a gene to wake up and spin strands of protein into pearls and globules that galvanise cells into action. Got some steak and chips coming down the pike? We’re going to need some amylase and lipase, stat. Chemical scissors that cleave our food into fragments, rendering it legible to our bodies. The necessity of digestive enzymes is self-evident. But what about stretches of genetic code that are less desirable? Like those that promote heart disease or type 2 diabetes?
For a long time, biologists believed that whatever was hard-coded into our DNA was an inevitability. That would mean that if you had a gene for heart disease, that gene would get woken up and it was only a matter of time before you had a heart attack.
But over the past 25 years, we’ve learned that this isn't the whole story. While we cannot change the sequence of As and Ts and Gs and Cs that we inherited, we can influence the sections of a gene that get woken up, or equally, the ones that stay in hibernation.
This means that, although we may carry a gene, or indeed several genes that increase our risk of cardiovascular disease, it’s not an inevitability that we’ll go on to have a heart attack or a stroke. If we can identify the factors that rouse protective genes, and lull unhelpful genes into a drowsy state, the thinking is that we can put that information to good use to improve public health.
It’s a cute theory.
This is the premise of the field of epigenetics. Biologists love to say that ‘genetics loads the gun but the environment pulls the trigger’. ‘The environment’ in this sense is diffuse: air pollution, water pollution, light pollution, noise pollution, childhood trauma, relational dynamics, access to care, housing, and our experiences of stigma or discrimination. Smoking, alcohol, drugs, and food can also influence which genes are woken up and which stay sleepy.
In the winter of 1944-45, Nazis blocked food entering The Netherlands, specifically in Western areas around Amsterdam. This caused an acute period of starvation, resulting in approximately 20,000 deaths, with already rationed food intake plummeting well below requirements. While pregnant people and infants were typically given more generous food rations, this period of famine meant that there was not enough food to go around, even for these vulnerable groups. Consequently, people who were pregnant suffered from acute malnutrition. This starvation resulted in epigenetic imprinting of babies born during this period.
When compared to babies born after allied forces liberated the occupied Netherlands, babies born during famine had a higher risk of poor health in adulthood. Specifically, they were more likely to be affected by cardiovascular disease and type 2 diabetes. The memory of starvation lived in their bodies, and so they were more likely to be a higher weight, their bodies proactively defending against any future bouts of famine.
The Dutch Famine Study, as it has become known, has become a classic ‘natural experiment’ in nutritional sciences that spurred the field of nutritional epigenetics. Nutrition, we now understand, influences how chromosomes unfurl deep in the belly of our cells, and whether genes will get woken up or stay sleepy.
The field of epigenetics seems to confirm what early Domestic Sciences advocates knew a century before the modern discipline was established: through careful calibration of our environment and lifestyle, we can promote human health and wellbeing.
This was the fundamental principle of Ellen Swallow Richards’ work. Recall that Richards was the pioneer of Home Economics in the US. According to Ann Oakley in The Science of Housework, Richards’ life was dominated by three themes: ‘a passion for science; the furthering of women’s education; and the home as a source for social change’. These coalesced around her attempts to raise domestic science to the same academic level as mathematics or chemistry.
Again, according to Oakley, Richards saw domestic science as ‘not only a means of elevating women’s capabilities but of ridding the world of all preventable disease and thus of creating a wonderful new one’. Richards herself wrote: ‘When wise attention is paid to municipal sanitation, to school hygiene, and household bacteriology, we may expect a social development hitherto Utopian’.
It is these same utopian ideals that underpin modern epigenetics. ‘Epigenetics is generally considered to be a basis for a better, more progressive, liberal and inclusive social policy’ sociologist Maurizio Meloni wrote in The Conversation. ‘If the environment is much more important than we thought in shaping our fate, there seems to be much more space to attack inequality at its root’.
Last week I shared an ‘uncomplicated’ history of nutrition and dietetics. By this I meant a version of the story with a straightforward narrative arc. It went like this – women, an oppressed class, were locked out of the halls of academia. And so, at a time when women were fighting for more rights, a group of pioneering home economists demanded that their work be considered a rigorous academic discipline. They were successful, and as a result, forged the disciplines of applied nutrition and dietetics, professions which are still dominated by women today. Read one way, this is a story of empowerment, liberation, and equality.
