Some may find it hard to embrace the fact that Prince Harry was born into a luxury, wealth and status filled life, purely due to who his parents are. For most mankind, hereditary has been a key basis for selecting our royal leaders. That’s not the American tradition of course nor the case across the animal kingdom.
Honeybees, for example, are well known for the way they treat their ‘royalty’; a queen bee enjoys a life of being fed, washed and escorted everywhere she goes. However, unlike Prince Harry, not every queen bee has won the genetic lottery. Her life of being tended to by loyal and devoted minions is a fascinating example of the role that nutrition may play in our health and development. The destiny of some bees who assume royal status can be influenced by how they are fed in their first days after birth—similar in ways to humans.
Food fit for a queen
Genetics is destiny in the majority of cases. The current queen lays fertilized eggs in each queen cell. However if the current queen dies, larvae must be taken from the dead queen. The timing of this process is critical. Until the third day all larvae are fed the same ‘royal jelly’ secreted from the heads of nurse bees. After this initial period, the majority are switched to a feed of pollen and nectar. Future queens however are handpicked to continue receive the royal jelly. It’s here that royalty is molded through nutrition, with the lucky few growing into the much larger and sexually promiscuous queen bees.
As scientists have found, the prolonged exposure of bees to royal jelly sets off a cascade of hormones from a liver-like organ that leads to the development of the reproductive system in the larvae. Some elements of the DNA of a fledgling queen bee, whilst still identical to a worker bee, are ‘switched on’ by the sustained presence of royal jelly. This process does not alter the DNA code itself, but acts via methylation of the DNA helix, which is the addition of small carbon groups to outside of the molecule.
These are referred to as ‘epigenetic’ changes and a simple way of picturing this is the DNA molecule as a book being ‘tagged’ with post-it notes. As development proceeds, certain tags are added while others are removed, a process whose dynamics depend on both our genetics and environmental stimuli. All this is repeated in every generation. For the most part, epigenetic modifications are reversible adjustments of gene expression.
The classical understanding of genetics is that our DNA is set in concrete from birth. We now know that’s too simplistic. Some research shows that epigenetic tags can be transmitted from one generation to the next. For example, when a mouse is conditioned to associate an odor with an electric shock, the mouse becomes more sensitive to that odor. This physiological response stems from epigenetic modifications of the gene that codes for the receptor for that odor. The mouse’s offspring often will demonstrate this same sensitivity to the odor, even though the offspring themselves have not experienced electric shocks
Similar to mice, humans and honeybees have a variety of tagging mechanisms that allow our genes to exist in communication with the outside environment, of which food is a major contributor.
Breastmilk: Dynamic messaging system
Humans, like honeybees, receive early dietary messages through breast milk and this may continue through every meal in our lives. As mammals, our nutritional messaging system is far more complex than found in honeybees. Various bioactive components, such as polyunsaturated fatty acids, have epigenetic influences on DNA that may assist in switching on complex gene expression linked to crucial early development.
With current recommendations suggesting to breastfeed for four to six months, breast milk has been found to shift in composition over this period in what may trigger various early genetic expression in a child. Interestingly, these changes do not involve basic nutritional elements such as fat, protein and carbohydrates. Instead they affect far more complex, bioactive components such as bacterial populations and immunological cells – both factors that extend far beyond the common understanding of nutrition constituting our dietary guidelines and recommendations.
At the very beginning of our lives, we receive an intricate epigenetic message from our mother that seem to influence life-long health outcomes. Research has linked this to better brain and immune development. Beyond childhood, these benefits extend to the lowered risk of communicable and non-communicable diseases like obesity.
Food for thought
Although our eating habits may not deliver us the life of a queen bee, our genes are interacting with food in ways we’re only beginning to understand. Although breastfeeding dictates crucial developmental stages, dietary habits play a key role in health with every meal representing a discussion with your genetic material.
Whilst there is much to learn, our new understanding of epigenetics shows how our body is designed to listen and adapt to environmental signals. Hence, every bite counts and you literally are what you eat.
Dr. Steven Lin (@drstevenlin) is a dentist, speaker and writer in the fields of health, dental medicine and nutrition. His current work explores the epigenetic, microbial and ancestral basis of oral disease. Find him at www.drstevenlin.com