weight loss

Note: In this article, the pros and cons of several different popular diets are discussed. I am not a dietician, medical professional, nor do I claim to be. This article is for entertainment purposes only. The opinions expressed are my own, and do not reflect the opinions or policies of the Gateway Region YMCA. Consult with a registered dietician and appropriate medical staff before beginning any nutritional program.

Few things in this world are as emotionally charged as our beliefs about food. What we eat positively or negatively impacts our lives in a big way. As such, discussing potential drawbacks with any particular diet can send fans of the diet it into a tizzy. Proponents of the nutrition program in question are quick to jump in and defend it, often quoting stats and studies they’ve memorized in preparation for such a moment.

Well, let’s avoid all those messy feelings, shall we?

The purpose of this article is to take a nutritionally-agnostic look at the pro’s and con’s of the most popular diets, as they relate to common health goals. I, the writer, have ZERO allegiance to any one school of thought.

So, without further-adieu, let’s take a look at some of the most popular diets as they relate to common fitness goals:


  • What is it?  The Paleo diet, popularized by Dr. Lorain Cordain, encourages participants to “eat like our caveman ancestors did”.  The idea being that we evolved eating a certain way, and the foods we consumed during our evolution are inherently better for us (this has been heavily debated). Eggs, meats, fruits, nuts and seeds make up the majority of foods, while refined sugar, grains, dairy, and processed other goods are avoided.
  • Does it work for losing weight? Well, sort of. If someone switches to a Paleo-style of eating after consuming of processed carbohydrates, added sugar, and excess calories, they’re likely to experience weight loss. The weight loss isn’t a result of anything magical about Paleo, but by switching to the foods allowed in Paleo (lean protein, fruit, seeds) people are almost always eating less overall than they were before. For example, 6 oz of lean steak and a handful of nuts has hundreds less calories than a pizza.
  • Does it work for athletes? The food groups in which Paleo calls for could serve many athletes well. Consuming lots of protein and carbohydrates via meat, eggs, fruit, and vegetables will work for almost any athlete, assuming they’re eating enough total calories. For endurance athletes, or those looking to gain lots of muscle mass, the restriction on refined sugar and processed foods can actually be detrimental (remember, we’re talking about performance in this instance, not health). Things like Gatorade, whey protein, and other athletically focused processed foods can enhance performance, but don’t abide by Paleo’s “pre-evolution” focus.
  • Conclusion: To say that the Paleo Diet is the most scientifically supported diet is a bit of a stretch. You see, our forefather’s came from all different corners of the globe, and as such, ate a wide-range of foods. Different animals, fish, plants, and nuts would have been unique to their diets based on where they lived. So, Paleo will look different for you, depending on where you can trace your genetics back to. Furthermore, most of the raw, unmodified, taken-directly-from-nature foods our forefathers ate simply don’t exist anymore.  But, that’s not to say the diet doesn’t have merit. The spirit of Paleo that is eating lots of lean protein, vegetables, and healthy fats is noble, and could serve many people well. Especially when switching from the typical American diet of processed carbohydrates and refined sugars, Paleo is almost certainly a more balanced option.


  • What is it?  Popularized in the 80’s and 90’s, the idea of reducing carbs is nothing new. Low-carb diets have been promoted under a variety of names: Atkins, Ketogenic, Mediterranean, South Beach and more all fall under the broad category of “low-carb”. Carbohydrates are the simple and complex sugars found in foods and drinks that our body uses for energy.  All carbohydrates, whether from whole-grain breads, fruits, or soft-drinks are converted by the body into glucose and glycogen and burned for energy (think of carbs as firewood and your body’s the furnace). The idea behind the low-carb diet is to restrict carbs, and force our bodies to find other energy sources to burn, such as body fat. 
  • Does it work for losing weight? In short, yes. Remember, losing weight is a mathematical equation: if you burn more calories than you consume, you lose weight. In reality, you could cut out any of the three main nutrients (protein, carbs, and fat) and lose weight simply because your total calories are going down. But, there are a few reasons that reducing carbohydrates is so popular, as opposed to cutting out protein and fat. Primarily, it’s because restricting protein and fat intake can be detrimental to health. Protein is our body’s main tool for repairing muscle tissue, and dietary fat is the raw material for hormone production. So, to restrict either of those nutrients could mean lost muscle mass or a dip in our natural hormones, neither being good for us.  Furthermore, because many people who use the low-carb diet have been eating lots of refined carbs and added sugar, cutting those out carries a swath of benefits. In addition to weight loss, reduced risk for heart disease, diabetes, and increased natural hormone levels have all been associated with removing processed carbs from the diet.
  • Does it work for athletes? This is a loaded question, and one that’s hotly debated among athletes and coaches worldwide. In short, a low-carb diets appear to hinder performance more often that they enhance it (there are exceptions).  You see, glucose and glycogen, which come primarily from carbohydrates, are your body’s preferred fuel source, especially for most intense activity. So, particularly for athletes who require long periods of aerobic activity, eating plenty of carbs is a likely good idea.
  • Conclusion: It’s probably fair to say that among the diets discussed here, the low-carb approach has the most data supporting its benefits. Weight loss and reduced disease risk have been widely attributed to reducing (not eliminating) carbohydrates.  It’s important to remember though, that carbohydrates have their place in every plan, especially for those of us leading an active lifestyle.


  • What is it?  The Vegan diet, not to be confused with vegetarian, is wholly void of animal products. Purveyors of this plan don’t consume meat, dairy, eggs, fish, or anything else that comes from a living breathing creature. By focusing on plants and plant-based foods, the vegan diet aims to improve health and body composition by eliminating many of the foods found in a typical American diet.
  • Does it work for losing weight? As with most diets that focus on whole foods and restrict processed carbohydrates, fat, and added sugar, the vegan diet appears promising for those looking to drop a few pounds. However, it should be noted that by eliminating so many foods, getting in the proper amounts of certain nutrients and micronutrients can be difficult for the inexperienced.
  • Does it work for athletes? To my current understanding, a vegan diet can work for an athlete, but that’s not to say it’s optimal. The simple fact that most athletes require so much protein (as much as .8 grams per lb bodyweight), vegan doesn’t appear to be the best choice for maximum performance. The protein bioavailability and density of animal products simply isn’t matched, ounce for ounce, by vegan foods.  That being said, there are some highly successful athletes who have been vegan or plant-based for years. But, the meticulous planning and strict eating schedule that allows them to succeed is significantly more complex than the other diets listed here.
  • Conclusion: The vegan diet is undeniably popular among those looking to lose weight and maximize health. Unlike the other diets discussed here, also has ethical implications for many individuals. Some vegan eaters choose the diet simply because they don’t support consuming animal-derived foods.  The vegan diet is often touted by proponents as being the “healthiest” diet plan, something that’s intensely debated among scientists and dieticians. It’s clear that there are drawbacks to completely eliminating large food groups. The bioavailability of vegan protein sources, and the potential for insufficient B and D vitamins are some of the chief concerns of the nutritional community.  Like all diet plans, vegan eating should only be taken on after consulting with a registered dietician.


Conclusion: Just tell me what the best diet is, already!

The truth is... there just isn’t one diet we can definitively label “the best”. Things like age, activity level, physical goals, and lifestyle will all play a major role in what style of eating works best. In the real world, the way most people eat more closely resembles a mixture of all the diets discussed here. For example, I consume vegetables, whole grains, fruits and nuts and avoid processed foods when possible, but also eat plenty of meat.

I would encourage readers to continue self-educating as much as possible. Be wary of “gurus” touting to have “the best” diet (these). Also, instead of thinking of foods as “good or bad”... think of foods in terms of “more and less”. For example, donuts aren’t bad or evil, but you should eat a lot less of them than you do vegetables.

The purpose of this article is to simply start the conversation around food, and highlight that while there are some universal truths (i.e eat less calories than you burn and you’ll lose weight), nutritional science hasn’t evolved to the point that we can prescribe one diet for everyone. So, never stop learning about food, speak to dieticians (not gurus) about your goals, and make the healthiest choices you can!

Written by: A personal trainer at the Gateway Region YMCA