Think you can’t build muscle as a vegan? Or that you can’t perform rigorous exercise on a keto plan? No eating style has a monopoly on helping you achieve your fitness goals. Here’s how you can leverage any diet – from keto to Paleo and even vegan – to work for you for maximum results.
When it comes to performance, every diet style has its advantages and disadvantages. Our dietitians examined five popular eating styles to bring you the pros and cons of each – plus, we make tangible recommendations on how to maximize your weight-loss, muscle-building or energy-increasing goals. Knowing the potential benefits and pitfalls of your eating style will help you tweak it for peak performance. To use this section, look for your preferred eating style and implement our pro tips on how to do it better. Alternatively, if you aren’t committed to any particular eating plan, check out all the styles and see which one best fits your fitness goals and eating tendencies.
On this high-fiber, antioxidant-rich plan, all fruits, vegetables, whole grains, nuts, seeds, legumes and soy products are encouraged. Bonus points for choosing whole, minimally processed versions to maximize your intake of vitamins and minerals. No animal products (meat, chicken, eggs, fish, pork, dairy or honey) are permitted on this plant-based plan.
PROS: Keeping plant foods in their unrefined, unprocessed state (thereby preserving fiber, antioxidants, vitamins and minerals) makes them excellent at working to decrease inflammation in the body and providing quality fuel for the good gut bugs that reside in your GI tract.
CONS: Plants often provide only small amounts of iron, B12, vitamin D and calcium, as well as some of the essential amino acids your body needs to make protein. Insufficient amounts of iron and B12 can impair energy production, making endurance workouts a bit tougher. Female athletes are at higher risk for low bone density.
WEIGHT LOSS: If you consume too many carbs from grains and fruit, this can increase the body’s production of insulin, and if you’re insulin resistant, this can act like a fat-storage hormone. If weight loss is your goal, consider increasing intake of protein (beans, lentils, edamame, tofu, seeds) and consuming fewer grains.
MUSCLE BUILDING: Most plant foods are missing certain essential amino acids, particularly leucine, that are key to muscle recovery. To counter that, consider increasing your intake of organic edamame, quinoa and pumpkin seeds to help with muscle recovery.
ENERGY: Whole plant foods are great for digestion, and high-fiber foods help create sustained energy.
MACRO GOALS: There are no firm recommended ratios, but we suggest 45 to 50% carbs, 20% protein, 25 to 30% fat.
Protein is essential for tissue repair and growth, but some proteins also act as enzymes that power chemical reactions and even function as hormones that help your body’s organs and cells communicate. Prioritizing foods like eggs, poultry, fish, beef, pork and organ meat as well as quinoa, edamame and tofu will ensure adequate intake. Opt for organic plants and organic pasture-raised/wild-caught/grass-fed meat and seafood for their anti-inflammatory benefits.
PROS: A high-protein diet that includes ample vegetables, low-sugar fruit, limited whole grains and anti-inflammatory fats may help lower blood pressure and reverse metabolic syndrome. Bioavailable protein (from animals) provides the building blocks for tissue repair.
CONS: Too much protein can crowd out essential fiber-rich plants, which contain anti-inflammatory properties that can benefit exercise recovery. Consuming fruits and vegetables at each meal will ensure adequate nutrients for recovery.
WEIGHT LOSS: As protein is very satiating, consuming fewer calories will encourage weight loss primarily from fat while providing enough protein to help spare lean tissue from being lost.
MUSCLE BUILDING: It can be easy to build muscle as there should be enough amino acids coming in for muscle protein synthesis. Building muscle comes from strength training, so limit daily or long cardio sessions as this can reroute nutrients away from muscle building.
ENERGY: Provided you’re getting carbohydrates from fruit, vegetables, nuts and seeds to balance out protein and fat, your energy levels should remain steady to power you through a tough workout.
MACRO GOALS: We suggest 30 to 40% carbs, 30 to 40% protein, 30 to 40% fat (carbs and fat should be equal to or less than the amount of protein).
This very-low-carb, high-fat, and moderate-protein diet focuses on animal protein, full-fat dairy, nuts, seeds and oils. Nonstarchy vegetables (such as leafy greens) and low-sugar fruit (such as most berries) have a small place on the plate. No grains, starchy vegetables, beans, sugar, low-fat dairy or high-sugar fruits are allowed.
The purpose of the keto diet is to put your body into a state of ketosis. This occurs after your body has burned through your stored carbohydrates (known as glycogen) and turns to fat for fuel. Fats are converted to ketones, which is an alternative fuel source for the body and brain. It can take days to weeks to get into ketosis, but once there, it makes losing weight much easier.
PROS: Fat is satiating. Keto eaters often report reduced hunger, and, as a result, they may consume fewer calories. Low carb intake can reduce blood sugar and insulin levels, which may reverse insulin resistance, type 2 diabetes and high triglyceride levels. If done correctly by choosing organic produce, anti-inflammatory fats and organic/grass-fed/wild-caught animal proteins, the keto diet can be anti-inflammatory.
CONS: The hardest part of the keto diet is the initial one to two weeks when your body is trying to switch fuel sources as you lose excess body water and electrolytes. Known as the “keto flu,” this phase can leave you feeling achy, fatigued and irritable. This may be remedied by adding a small amount of extra salt to the diet, as well as increasing intake of magnesium through supplementation. Like any diet, it’s easy to negate the health benefits by choosing poor-quality fats and eating too many keto treats. When you do add carbs back to your diet, some weight will return.
WEIGHT LOSS: Feeling fuller for longer and consuming fewer meals and snacks should translate to weight loss. In the early phases of the keto diet, consider keeping exercise low-impact (walking, yoga and stretching) as your body adjusts to burning fat for fuel. Once in ketosis, you should be able to perform any type, intensity and duration of exercise.
MUSCLE BUILDING: Although a traditional keto diet is relatively moderate in protein, switching to a higher-protein keto diet will provide enough essential amino acids to repair and grow muscle tissue when paired with a more demanding strength-training program.
ENERGY: With fewer carbs coming in, you should see more stable energy levels as blood sugar levels may also become more even-keeled. Make sure to add electrolytes (sodium, potassium, magnesium) to help prevent keto flu symptoms and improve energy. Often, people in ketosis report improved clarity, energy and exercise performance.
MACRO GOALS: Unlike the other diet styles that have more flexibility in their macros, the keto diet is fairly strict in this respect. We recommend 5 to 10% carbs, 15 to 20% protein, 70 to 80% fat. Some experts recommend keeping total carbs at less than 50 grams per day, though there are differing opinions on the precise number.
The Paleo diet is based on foods similar to what might have been eaten during the Paleolithic era, which dates from approximately 2.5 million to 10,000 years ago. Foods allowed on the Paleo diet include anything that can be plucked from the ground, picked off a tree, hunted or fished. This includes all fresh fruit, vegetables, grass-fed animals, wild-caught fish, eggs, nuts, seeds and spices. No dairy products, legumes, grains, soy, refined sugar, artificial sweeteners, vegetable oils or processed foods are permitted.
PROS: A well-formulated Paleo diet may improve blood pressure, blood sugar and triglycerides, decrease insulin resistance and inflammation, and promote fat loss.
CONS: The absence of whole grains and legumes, which are considered good sources of fiber, vitamins and minerals, may negatively affect energy levels and impact performance in endurance-type exercises. Many people think Paleo means high protein, so they overemphasize protein while not consuming enough plants. Aim for a balance of protein, carbs and fat from minimally processed sources.
WEIGHT LOSS: A workout regimen that alternates days of high-intensity interval training (HIIT) and strength training paired with a Paleo diet that favors more protein and fat and slightly fewer carbs should promote a steady reduction in body fat.
MUSCLE BUILDING: Paleo diets are better geared for strength training (weight training, body-weight training, CrossFit or resistance training). The damage to muscle tissue that occurs during these types of training is more easily repaired with a diet such as Paleo, which supplies bioavailable protein at each meal.
ENERGY: Meals that are macro-balanced and consist of nutrient-rich foods are excellent sources of vitamins and minerals, which aid in energy production.
MACRO GOALS: There are no firm macronutrient targets as the diet can be low/high carb, low/high fat and/or low/high protein. We suggest aiming for 30 to 40% carbs, 20 to 30% protein, 30 to 50% fat.
A flexitarian diet is predominantly a plant-based diet with the occasional inclusion of animal protein (think flexible + vegetarian). There is no minimum or maximum quantity of animal protein, but you should aim for cleanly sourced products – such as organic, grass-fed and wild-caught.
PROS: Choosing plenty of antioxidant-rich fruits, vegetables, whole grains, legumes, nuts and seeds balanced with enough fish, eggs, poultry and beef, will help build an anti-inflammatory diet that may promote weight loss and help improve energy. No limitation or elimination of entire food groups means this diet should be easy to stick with for the long haul.
CONS: If your diet consists of foods that are predominantly refined (think white potatoes, white rice, pasta, bread), contain sugar or too much dairy, and are low in fruits, vegetables and animal protein, it can promote inflammation and may result in elevated blood sugar, insulin and weight gain. Diets high in refined grains may negatively affect energy levels, impairing exercise performance.
WEIGHT LOSS: Slow, steady weight loss is achievable when prioritizing high-fiber veggies over fruits and whole grains and combining them with protein and healthy fats. A flexitarian diet matches well with aerobic exercises (walking, running, cycling, swimming), strength training, as well as yoga and Pilates.
MUSCLE BUILDING: A macro-balanced flexitarian diet should provide enough fuel for strength-training workouts and recovery. A post-workout meal should contain 20 to 30 grams of protein, preferably from animal protein.
ENERGY: Expect to see good energy production, as plants contain high levels of micronutrients (vitamins and minerals). Energy level should stay more consistent if macros are balanced (see below).
MACRO GOALS: There are no firm recommended ratios, but we suggest 40% carbs, 30% protein, 30% fat.
Read more about the advantages (and disadvantages) of various diets:
- How to Thrive on a Vegan Diet
- Deconstructing the Flexitarian Diet
- Understanding Trending Diets
- There’s a New Version of Whole30 — and This One Is Fully Plant-Based
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