School is back in session! Summer has ended and has taken all of my free time with it. But I am excited and am welcoming the change in seasons with open arms. My classes are so, so interesting and it is my last year as a dietetics student, which is definitely something to celebrate! It seems like just yesterday I was beginning my first class in chemistry, trying to teach myself how to add and subtract again and having a huge lack-of-confidence for the big life change I was undertaking. I am so glad I took the jump; I can’t imagine doing anything else.
So anyways, back to how much I love my classes. I have really enjoyed all of my past nutrition classes, but this year takes everything to a whole new level. We are digging deeper into clinical nutrition, macronutrients and micronutrients, and practical uses of our knowledge. We have been forming a solid foundation in dietetics for the past two years, and now is the time where we can grow that foundation and begin to think more critically. For the first time I feel like I know some things. Some things. Huge emphasis on the “some”. Nutrition is one of those fields you can never truly know everything about: a big reason I love the field as much as I do.
We will be studying many things this year: biochemical assessments, eating disorders, motivational interviewing, the major nutrition-related disease states like diabetes and cardiovascular disease, etc. One of the subject areas I am most excited to learn more about is nutrigenomics.
Nutrigenomics. It even sounds cool. What the hell is nutrigenomics, might you ask? Well, for those of you who may be nerdy like me, read on and let me tell you what I know.
It is well understood in the nutrition profession that “individual nutrition” is the gold standard in terms of practice. We all have different preferences, lifestyles, values, goals, and experiences and we need to cater to those differences. A big reason fad diets don’t work is because they tell everyone to eat the same way and have very little room for individuality. People fail because it may not be right for them. (Or the diets are calling for only eating three apples a day and a spoonful of peanut butter and no one wants to die of starvation.) Gluten-free doesn’t work for everyone and neither does the Caveman diet. We are all different, but we are also all very much alike. In fact we are 99.9% identical to the person sitting next to us. Which blows me away every time I think about it. But that .1% is what separates all of us. It is what makes you you. It is what gives you a weird, slightly droopy left eye and it is what makes you predisposed to certain diseases. It is why you might develop Type 2 diabetes by eating a certain way, but your best friend who eats the exact same way might not. It is why your grandpa who has smoked two packs a day ever since he was 12 has never developed lung cancer, but your uncle who smoked much less dies from it.
Which brings me back to nutrigenomics. By definition, nutrigenomics is an emerging science focused on how food affects gene expression (our phenotype). It describes how what we eat influences our bodies at the genetic level. And as we all learned in 6th grade science, genes determine our characteristics. They determine if we are predisposed towards certain illnesses, how we respond to caffeine, or what size our bodies operate best at. Ever wonder why certain people can seem to “eat whatever they want and never gain an ounce” but you eat a piece of chocolate cake and store it until next year? It’s all in your genes. Nutrigenomics studies how food affects that .1% variation in our genes.
Nutrigenetics (in contrast to nutrigenomics) is how our genotype influences our response to the foods we eat. It explains why someone who eats a high fat diet can have elevated levels of cholesterol while another person has the exact opposite response. It is the other side of the same coin when talking about nutrigenomics.
So, genes determine function. Is that it? What we got from our momma is what we have to work with? Scientists and researchers are now saying no. Yes, they are heritable traits, but also, yes, they can be messed with. There is extremely strong evidence that nutrition and lifestyle choices (such as smoking, exercise, alcohol consumption, etc.) can modify how certain genes are expressed. So, for example, let’s say Frank has a history of colon cancer in his family and unfortunately he has that same gene. Chances are likely of Frank going down the same path. But, if we can pinpoint that gene that controls whether or not Frank will actually develop the disease, and then treat that gene with specific nutrition therapy, we may be able to control if Frank has to suffer at all.
We now know it is true that there are certain bioactive compounds in food that have the ability to turn specific genes on or off. Researches everywhere are currently studying the foods that do this and how we can use them to prevent and/or treat certain nutrition-related diseases. For example, the polyphenols in red wine seem to be protective against heart disease. What can we learn from this? Drink more red wine, duh.
The question is now, how can we use the study of nutrigenomics and nutrigenetics to help our populations? Currently, dietary reference values are set for the specific nutrients necessary for optimal health. It’s what all of those numbers mean on the back of your cereal box. But not everyone will function optimally with those recommendations. Some people may need more potassium than the general population while someone else cannot tolerate the current amount of sodium recommended. Eventually, nutrigenomics may be able to be the missing link in all of those variations. It may be able to make up for the discrepancies found in various health outcomes in our communities. For the field of nutrition and dietetics, it is huge. I can foresee it one day allowing healthcare professionals to better tailor nutrition advice for patients and clients. As opposed to giving someone a typical recommendation based on the current reference values (and possibly either hurting or at least not helping that person), perhaps one day I will be able to personalize that recommendation a bit more.
With our rates of nutrition-related illnesses and disease states on the rise every day, it is crucial we begin to look at better options for treatment, and especially prevention, of these issues. Five of the top ten causes of death in the U.S. are nutrition-related. Heart disease and cancer account for close to 50% of those deaths. We need more tools in the search for a solution and I believe nutrigenomics can help us with that.