Dieting can be an intimidating challenge for those unaccustomed to it. Especially given the level of misinformation on the internet from “fitness influencers” concerning nutrition, it often feels as if there is nowhere to turn for scientifically accurate information on dieting.
However, creating a nutrition plan does not have to be difficult once the science of dieting is explained as a highly individualized process of trial and error.
This is why most people interested in dieting ought to avoid any diet that begins with “the,” has a middle word such as “keto,” “paleo,” or “Mediterranean,” and ends with the word “diet,” as in most such cases, these so-called diets are merely marketing gimmicks with no basis in science.
That is not to say such diets cannot be enjoyable and have no place for specific health conditions. For example, some forms of cancer feed predominantly on carbohydrates, making a ketogenic diet –mainly composed of fatty acids– ideal for such a situation.
But in most cases, fancy “diets” of this sort are unnecessary at best and proven wrong by science at worst through extensive retractions of studies.
Instead, this article will take a deep dive into science-based approaches to human nutrition.
The first important factor to note in dieting is that unique bodies –which each human body is– require special diets, with some overlap in most cases.
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What is a Personalized Diet Plan?
Nutrition is at the core of human health. However, because not everyones’ personal health goals align perfectly, creating a nutrition plan is a highly – though not entirely – personalized endeavor.
For example, an athlete has health goals – such as improving performance, strength, and power – that non-athletes lack, making for markedly different nutritional requirements between athletes and non-athletes.
Likewise, many non-athletes may have unique health conditions that require them to deviate from recommended daily allowances of macronutrients (fatty acids, carbohydrates, and protein).
In the vast majority of cases – barring unique health conditions like allergies or auto-immune disorders – an ideal meal plan derives from whole food sources, consisting of fruits, vegetables, and lean animal proteins, such as eggs, fish, and Greek yogurt.
This is because such food sources are high in micronutrients (otherwise known as vitamins and minerals), which are vital for human health.
Vitamin and mineral deficiencies are exceedingly common causes of physical and mental health conditions. As such, for most people, a diet plan should center around eating food rich in vitamins and minerals for most meals.
Still, most nutritional scientists do not recommend being too strict in this respect. For example, according to Dr. Eric Helms, the most critical aspect of ensuring a diet plan works is that it is a sustainable diet plan.
Most people are unaccustomed to eating “healthy” nutrient-rich food and, therefore, will find starting a habit of doing so rather challenging.
To make this sustainable, nutritionists and dieticians often recommend that those on diets follow an 80/20 rule. In other words, these health professionals recommend that you get 80 percent of your calories from nutritious foods and the rest from whatever foods you enjoy.
Understanding individual health needs
What it means to have individual health needs is not entirely contingent on whether or not you are sick or have a condition, such as an auto-immune disorder, that may require highly-specified dietary changes.
For example, athletes will require 0.8 grams of protein per pound of body weight to support muscle growth, maintenance, and athletic performance.
Non-athletes, according to University of Illinois Food Science Professor Donald Layman, need only 0.8 grams of protein per kilogram of body weight each day to prevent protein deficiencies but can reap unique health benefits by doubling this daily requirement.
And for individuals – whether athletes or not – with specific health conditions, speaking with a nutritionist and dietician is essential to formulating a personalized nutrition plan. Gurus on the internet are bound to mislead such individuals down the wrong path, which can be dangerous.
Again, for most people, you can’t go wrong with eating lots of fruits, vegetables, and lean protein. However, for those with specific health goals, you should adjust from this baseline according to your self-evaluation as guided by an expert in human nutrition.
How many calories do you need a day?
The number of calories each of us needs daily depends on several factors. For example, how much we move our bodies, how much we weigh, and what we want to do with our weight –i.e., gain, maintain, or lose– will determine the number of calories we need each day.
Luckily, we do not need to leave this guesswork up to individual speculation or online trends, as there are now mathematical calculations we can use to determine the number of calories we need to consume each day to meet our health goals.
One of the most highly respected equations of this sort in the world of nutrition is known as the Mifflin-St Jeor Equation, which is as follows:
Formula
Women: (10 * weight [kg]) + (6.25 * height [cm]) – (5 * age [years]) – 161
Men: (10*weight [kg]) + (6.25*height [cm]) – (5 * age [years]) + 5
Multiply the result to accommodate for activity levels:
Sedentary *1.2
Lightly active *1.375
Moderately active *1.55
Active *1.725
Very active *1.9
Before multiplying it by our activity levels, the result of this formula is known as our basal metabolic rate (BMR), which is the number of calories we burn each day while the body is entirely at rest.
When multiplied by our activity levels, the result is what is known as our total daily energy expenditure (TDEE), which is the number of calories we need to consume each day to maintain our body weight.
Hence, when we are interested in gaining or losing weight, it is our TDEE that we must manipulate. Generally speaking, to gain muscle, we should eat no more than 250 calories above our TDEE and lose fat no less than our BMR.
Due to the 1st-law of thermodynamics, this calculation is all you need to know when it comes to the goal of losing, maintaining, or gaining weight. Indeed, any combination of fats, carbs, and protein will do the trick for any of these goals as the calculated calorie intake is sustained over time.
Apart from personal health concerns, limiting any particular macronutrient from your diet plan is no reason. However, in cases where individuals might see such limitations as necessary, asking a doctor for guidance is highly recommended.
How to Meal Prep
Once your calories have been calculated, how to create a nutrition plan becomes relatively straightforward. All it takes is counting calories on packaged foods or looking into databases of food items without nutritional fact labels on them, such as produce.
Once you have a calorie goal each day, your job becomes hitting that calorie goal in this manner.
Some prefer using helpful apps that count calories for you, like Myfitnesspal, but manually depending on a calculator by looking at labels is a surefire way to access your daily food intake accurately.
This can make it easier to adhere to a diet because it allows us to be prepared for what we will eat each day, making us less likely to eat out and, consequently, deviate from our diet plans.
In keeping with Dr. Helms’ principle of adherence, keep in mind that the time you eat during the day is irrelevant to your end goals. If you prefer skipping breakfast, skip breakfast. If you love breakfast, chow down in the morning.
That will make dieting much easier without any difference in results.
Evaluating the Evidence
Nutritional science is an exploding field. Therefore, new research is being worked on daily, generating new theories on well-known concerns. Sometimes, these results create conflicting information – especially when the media report on studies on nutrition.
We can evaluate whether we should concede such evidence based on the quality of the research done on a particular topic.
Suppose a theory is repeatedly proved correct and has meta-analyses supporting this replicability. In that case, the theory is unlikely to be proven wrong anytime soon –the 1st-law of thermodynamics comes to mind here.
By contrast, a single study is insufficient to prove a theory is correct. Instead, scientists must replicate it several times before it can be trusted as a valid theory.
But who has the time to evaluate scientific claims at this level? Most people don’t, but nutritional scientists and dietitians do.
Hence, if you want to delve deeper into the science of human nutrition –what it takes to truly optimize the process of creating a nutrition plan– here are 12 fulfilling careers for health-conscious individuals that will help lead you in that direction.