The best human diet is something that many people seem to be searching for. Reams have been written on nutrition forums in often heated debates over the finer points of what makes the best diet. It sometimes seems that vegans and followers of whatever the latest low carb diet is called (Atkins, paleo, keto, carnivore, whatever) are at war. But today I am going to set the record straight on what is the best diet, drum roll please… it doesn’t exist, at least not in the objective way you would expect, and moreover even if it did it wouldn’t matter. I will reveal the real best diet at the end.
First, why is there no best human diet? Well obviously we are all different: we each have different genetics which means that we each need slightly different ratios of both macro and micro-nutrients, we have different gut micro-biomes which effect how we digest and absorb nutrients; we also each have different activity levels which affect our caloric needs. What this means is that it is impossible to create one diet that is perfect for every single person on this planet. Now, what about the bespoke diet plans? Well, we are actually so different that the best possible diet for you today is not the same as it was yesterday. You will burn different amounts of calories from day to day, you will need slightly different amounts of minerals and vitamins depending on which part of your body was exercised the most, if you were sick, and even depending on the weather and the seasons. So even if you went with an ultra bespoke genetic testing diet plan it will not be perfect; and yes, that is a real service. The human organism is also adaptable; this means that our bodies can find ways to thrive on many different diets, regardless of our individuality. It also means that such “perfect” plans are unnecessary overkill.
But let’s say for the sake of argument that at some point in the future nutritional science becomes advanced enough to allow the creation of a 100% perfect meal plan for you, would it matter? The short answer is “No”. Why not? First, you are very unlikely to keep to it 100%. With all we know already about nutrition people still buy and eat crap that they know isn’t good for them, more information isn’t going to change that. And unless you are a pro-athlete trying to eke out the 0.1% increase in performance needed to go from no medal to gold, a 100% perfect diet won’t even make a difference to you. But there’s more, even if you do manage to stick to your “perfect” meal plan, you won’t even be consuming it. This is because there are huge levels of variation in natural unprocessed foods [1]. If you pick two apples from the same tree likely hood is that they will be different weights, but even if they are the exact same weight and size their nutrient contents will differ, one might have got more sun and created more antioxidants, or the other could have been in a more favorable position on the tree and absorbed more nutrients. And there is no way to know if your apple meets the specifications of the apple in your meal plan because the tests that can determine the nutrient content of your food are destructive, so you would not even be able to eat that apple after you discovered it was the perfect one. Highly processed foods have far lower levels of nutritional variations, but they also have far lower levels of nutritional value, so consuming a diet of real food that is nutritionally adhering to a meal plan is impossible.
The pursuit of the perfect diet is actually harmful. If you read my last blog about the Bell Shaped World you will know about diminishing returns, taking your diet from 10% healthy to 20% is going to make a much bigger difference to your health than taking it from 90 to 100%, or even 80 to 100%. And you would also know how too much of anything is harmful because it takes away from other things that could benefit you. The effort you are putting into discovering what your perfect diet is and improving it that last 10% would be better spent improving other aspects of your health: such as sleep or exercise that you may have let lag behind. This is especially true when it comes to your social health; which is actually one of the biggest predictors of future health[2]; but if you are trying to perfect your diet this is one of the biggest sacrifices you will have to make. It makes it impossible to eat out, to have a casual bite with friends; it even makes it harder to travel because trying to find perfect foods is almost impossible at home, let alone when you are somewhere new and don’t know where to look. The fact that these social sacrifices have to be made means that the pursuit of the perfect diet negatively effects the very purpose for doing it: living a long and healthy, happy life. It is also better for your long term health to stick to 60% healthy diet all of the time, than a 100% perfect one some of the time, with binging when will power fails (which seems to be a common approach to dieting)[3].
Ok, so enough negativity, if the perfect diet does not exist and if trying to get to it is harmful, what should we do? Should we just give up and eat whatever processed crap we want? Of course not, we have to make small incremental changes to our diet that compound over time. And this, ladies and gentlemen, is the promised best diet for you today. It is the healthiest diet that you can stick to over the long term. And this will actually change over time, as you get used to each change that you make your tastes and preferences will change to, vegetables you once thought were disgusting don’t taste so bad anymore; allowing your subjectively best diet to slowly approach the objectively perfect one. In my next blog I will be going over my preferred method of doing this.
Citations
1 Vitamin C content of foods: sample variability
J T Vanderslice D J Higgs
The American Journal of Clinical Nutrition, Volume 54, Issue 6, 1 December 1991, Pages 1323S–1327S, https://doi.org/10.1093/ajcn/54.6.1323s
Published: 01 December 1991
2 A longitudinal study looking at and beyond care recipient health as a predictor of long term care home admission
Raquel S. D. BetiniEmail authorView ORCID ID profile, John P. Hirdes, Donna S. Lero, Susan Cadell, Jeff Poss and George Heckman
BMC Health Services ResearchBMC series – open, inclusive and trusted201717:709
https://doi.org/10.1186/s12913-017-2671-8© The Author(s). 2017
Received: 11 April 2017Accepted: 3 November 2017Published: 9 November 2017
3 Int J Exerc Sci. 2009; 2(3): 191–201.
Published online 2009 Jul 15. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4241770/
PMCID: PMC4241770
NIHMSID: NIHMS594583
PMID: 25429313
Consequences of Weight Cycling: An Increase in Disease Risk?
KELLEY STROHACKER,† KATIE C. CARPENTER,† and BRIAN K. MCFARLIN‡