This post will be part one of a three part post series going over the controversy of the ‘best’ diet.
You make more than 200 decisions in a day—which phone to buy, where to go for vacation, who to date. Obviously these are questions that require tons of deliberation. The general quality of your life is often determined by questions that seemingly have little significance but carry a huge consequence. How about another question that we always ask ourselves, one that has the capability to have an enormous impact or none at all?
“What is the best diet?”
Again, right? Source
Of the hundreds of decisions you make per day, approximately 226 decisions will be about food (Wansink). Due to the propensity of food decisions in your daily lives, it goes to say that such a question is riddled with endless loopholes, criticism, lies, and truth. It’s talked about so commonly that you can just shrug it off, but the importance is scarily deceiving. Most importantly, the significance of this question lies within the context of the person asking it, because certainly, the idea that a perfect diet exists to fit everyone’s wants and needs may be nothing but a false truth.
And if you work in a field that is intricately involved with human health, disease, and nutrition—like a Registered Dietitian (RD)—it’s the worst possible question. Dealing with a question that is entangled in a web of this and that is difficult enough to write in a blog post, imagine trying to explain it to a person who has no clue. RDs deal with not luxuries people think about once every few years like buying a house or car, but a commodity, and their responses directly affect those 226 daily food decisions people make. And because this question has been asked so many times and approached in so many different ways, the significance of it is slowly beginning to lose out to the myriad of options available in the mainstream.
Wrapped up nicely with the “what is the best diet” are a couple of other multi-faceted questions that you probably want answers for sooner than your birthday.
“What are the best foods to eat?”
“What’s the best way to do [insert goal here]?”
So on and so forth. The best diet would be the best present ever. Although it makes sense that there is no one best diet and no one best food, these questions cannot be proven through science. If it could, then scientists would still not be spending hundreds of man hours and thousands of research grant dollars trying to figure out what the optimal diet is. Fortunately, science does shed light on the path you should take to achieve good health through diet.
For your next birthday. Source
THE MAZE OF DIETS
Follow any large media outlet and you’ll be sure to read, hear, or smell reports and journalists talking about whether you should “slash carbs to carve a sleek and sexy six-pack” or “drop pounds by dropping fat” or “eat like a caveman and look like one” (uh, do you actually want to look like this?). So much conflicting information, so little time—who to listen to?
It’s the grass-fed, organic, free-range, non-GMO, pastured limestone that helps him maintain perfect white teeth (source)
Outside of the lab, many camps have laid claim to a best diet, but no one seems to agree with each other fully. One study will come out today that refutes yesterday’s study on the same diet. On the vast intranet, you have various nutrition experts and armchair gurus going to war on their keyboards espousing their preferred diet without tickling the thought that their diet may not actually be the best. The devil is in the details, so asking a layperson to read a full article and understand the meaning of those details is like asking a dolphin to walk on land—it’s not going to happen. That’s why there’s the media to help, except they really don’t. Your best bet is to look for someone who actually reads and keeps up with the literature—say a doctor or an RD. Luckily, I do enjoy a good read and turning the knowledge of science into application is a passion of mine. Very basically, let me answer the almighty question, “which is the best diet”. And it is… <drum roll>
The Mediterranean diet.
A low-carbohydrate diet.
A vegetarian (or vegan) diet.
The Dietary Approaches to Stop Hypertension (DASH) program.
The Paleo diet.
… Hold the phone! Didn’t I just say that I would tell you what the best diet is? Why, yes, I did, and I did. I know that best is a term to denote a singular thing that is superior to all others in its respective category, but read on to find out why everything can be the best.
LET THE RESEARCH SPEAK
The topic of what diet is best is probably one of the hottest in nutrition research and a new study (and book) is published just as quickly as a baby is born. According to the research, it’s fine to contradict myself. Why? Because each diet is the best. Before we move onto why each diet can be the best, let’s look at very briefly what some of the recent research actually has to say in favor of the major dietary regimes and their spin-offs:
The Mediterranean Diet—one of the “children” from a combination of research and observation, the Mediterranean diet seeks to reflect the dietary habits of some of the healthiest people in the world. Unlike most dietary programs, the Mediterranean diet is one of the few scientifically studied that attempts to mimic what is actually consumed in observation. Specifically, the Mediterranean diet emphasizes fish, nuts, legumes, fruits, vegetables, and low glycemic carbohydrate sources. In the literature, a Mediterranean diet is similar to a moderate carbohydrate diet, about 40%. Some benefits:
- Increased life span (Crous-Bou, 2014)
- Decreased weight and obesity (Sayon-Orea, 2014; Huo 2014; Thomas 2007)
- Improved non-alcoholic fatty liver disease (Zivkovic, 2007)
- Improved hemoglobin A1c and other diabetes markers (Carter, 2014; Huo, 2014; Esposito, 2014)
- Improved blood lipid panel (Huo, 2014; Richard 2014; Thomas, 2007)
- Decreased risk of certain cancers (Whalen, 2014)
Low-carbohydrate diet—popularized mainstream by Robert Atkins, MD, this dietary protocol has really been in practice throughout mankind’s history. There are various societies that consume low daily carbohydrates, such as the Inuits. Because of carbohydrate’s ability to affect various health markers such as blood sugars, it is being more commonly manipulated, and with good results. Low carbohydrate diets can be characterized in the literature as anything under 40% and as low as 5% of total calories.
- Improved satiety (Gibson, 2015; Erlanson-Albertsson, 2005)
- Significant weight loss, even against FDA approved weight loss drugs (Yancy 2010; Yancy, 2004; Sharman, 2004; Bertoli, 2014; Tay 2008)
- Improved blood lipid panels, especially in those with high triglycerides (Yancy, 2004; Thomson, 2010; Sharman 2004; Volek, 2008)
- Improved diabetes markers, especially in those with compromised insulin sensitivity (Samaha, 2007; Feinman, 2015; Arora, 2005)
- Decreased inflammation and tumor growth (especially in response to ketogenic diets)(Ho, 2014; Klement, 2011)
Low-fat diets—programs such as Dietary Approach to Stop Hypertension are those purported to improve blood lipids under the premise that saturated fat and cholesterol increase risk of heart disease and blood pressure. There is extensive evidence that free-living populations do follow a somewhat lower-fat diet and this can also include those who are vegetarian. Asian populations typically consume a diet lower in fat, for example. Fat content is usually below 30% and carbohydrates are higher, above 50%.
- Decreased weight and obesity (Astrup, 2000; Astrup 2002; Hooper, 2012; Mueller-Cunningham, 2003; Tay, 2008)
- Improved diabetes markers (Yokoyama, 2014)
- Improved cardiovascular health, such as blood pressure and blood lipids (Yokoyama, 2014; Shridhar, 2014; Famodu, 1998; Nosova, 2015)
- Improved inflammatory markers (Turner-McGrievy, 2014; Egert, 2014)
- Improved non-alcoholic fatty liver disease (Ma, 2015)
- Decreased risk of certain cancers (Fung, 2010)
Paleolithic diets—the attempt to emulate how our hunter-gatherer ancestors ate. “Paleo” diets have gained an immense surge of popularity since the late 1970’s when a seminal paper was produced citing anthropological data that our hunter-gatherer ancestors ate quite differently than how we are currently eating. Supporters of this program propose that by eating lean meats, vegetables, fruits, nuts, and seeds, and excluding dairy, legumes, wheat, and grains, we will see a boost in our health and performance because we will be eating concomitantly with our genetic makeup. Research does not give a clear macronutrient breakdown of a paleo diet, only that the program fits within the framework of the paleo principles mentioned above.
- Improves weight loss and obesity (Boers, 2014; Mellberg, 2014)
- Improves satiety (Jonsson, 2013; Jonsson, 2010)
- Decreases risk of certain cancers (Whalen, 2014)
- Improves cardiovascular risk factors (Jonsson, 2009; Klonoff, 2009)
- Improves diabetes markers (Frassetto, 2009; Klonoff, 2009)
- Improves metabolic syndrome characteristics (Boers, 2014; Lindeberg, 2012)
“THE RESEARCH HAS SPOKEN… AND I’M STILL CONFUSED”
The above is just a small handful of proposed health benefits of each diet. There are seriously hundreds of thousands of studies on each diet and their derivatives; it’s no wonder the average person has no clue where to start when it comes to which diet they should follow. I also refrained from going into the demerits of each diet because I do not want this post to be the length of half a book. Despite the small list, do you see a pattern? Here is the bottom line and the answer you have been waiting for:
Any diet will work. Any diet has the potential to be the “best diet”. And not surprisingly, each eating pattern overlaps with one another in some aspect of health, whether it’s improving diabetes, cardiovascular disease, or weight. The researchers in each study were looking at a particular end point, because frankly, it will be nearly impossible to study how each food affects each health biomarker, especially in context of individual differences. Nonetheless, each diet possessed the ability to improve health to a statistically significant degree.
Stay tuned to read how to connect the ‘best’ diet to your situation.
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