Consider this your FAQ on these low-carb diet plans.
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Unless you've been living under a rock for the past few years, chances are you've heard about meal plans like the raw foods diet, the IIFYM diet, the paleo diet, and the ketogenic diet. Those last two, in particular, have become quite buzzy recently due to their focus on low-carb eating, but what characteristics set these two eating styles apart? Here, we're diving deeper into the difference between the Paleo diet and the keto diet, so you can choose which (if either) is the right eating plan for you.
What Is the Keto Diet?
The keto diet basically involves eating lots of healthy fat and very few carbohydrates in order to change the way your body sources energy. By eating very few carbs, your body won't grab the limited amount of glucose, an energy reserve and resource from the breakdown of carbohydrates. Instead, it will source energy from fat, using ketone bodies. The keto diet guidelines recommend you get roughly 75 percent of your calories from fat, 20 percent from protein, and 5 percent from carbs. After a few days following this plan, your body will enter "ketosis," meaning it's officially using fat for fuel.
What Is the Paleo Diet?
The paleo diet involves eating like your hunter-gatherer ancestors would have eaten during the Paleolithic era. People who follow a paleo diet avoid grains (including bread, rice, pasta, quinoa, and more), beans and legumes, soy, dairy, refined sugars, and certain oils, says Cara Harbstreet, M.S., R.D., of Street Smart Nutrition. Other off-limit foods include meat with any hormones or antibiotics, and processed foods (especially those containing preservatives). So, what's left? Generally speaking, paleo dieters load up on lean meat, seafood, seasonal veggies, some nuts, and fruit. Anything cavemen could gather or hunt is fair game.
One easy way to understand the difference between the paleo and keto diets is what they are designed to do: Keto is crafted specifically to get you into ketosis, and paleo is more aimed at bringing eating back to basics.The biggest similarity between the two? They are both restrictive diets.
Still confused about exactly what to eat on either diet? Or how the guidelines, meal plans, or results might differ? This Q&A should help clear things up.
1. Does it restrict calories or set portion sizes?
Keto: No. What matters in keto is your macro ratio: 75 percent of your calories from fat, 20 percent from protein, and 5 percent from carbs. The diet leaves you free to decide your optimal calorie intake.
Paleo: No. You can decide for yourself how much caveman-style food to eat.
2. Are certain food groups off-limits?
Keto: Yes. Because the diet mandates that only 5 percent of your daily calories come from carbs, it seriously limits your intake of healthy whole grains like brown rice, quinoa, and oats. Plus, a number of fruits are off-limits—apples (besides tart Granny Smith), bananas, and grapes are no good to name a few, while berries are fair game.
Paleo: Yes. Generally, you're restricted from anything your ancestors couldn't hunt or gather, but there's some room for debate about what exactly that entails. But for the most part, paleo pros say to avoid cereal grains, legumes (that includes all beans), dairy, refined sugar, potatoes, processed foods, overly salty foods, alcohol, and refined vegetable oils. Some paleo proponents argue that things like grass-fed butter are reasonable additions to the diet. (Related: Meal Planning Tips That Make Paleo Eating Easier)
3. Is the diet meant to be a long-term lifestyle change?
Keto: Many people try the keto diet as a quick way to lose weight, as carbs hold a lot of water, so depleting your intake can reduce bloating and help you lose water weight fairly early on. However, because of the dietary restrictions, experts (even those who are fans of the keto diet) suggest it as a temporary eating style, not a forever way of eating. With the exception of following a keto diet to control seizures, many people will stop keto entirely or go through carb cycling.
Paleo: Some people try paleo as a short-term, Whole30-type experiment. Others are in it for the long haul. "There is little long-term research about the effects of the paleo diet," says Harbstreet. "One hypothesis is that although short-term health benefits may be seen, the long-lasting effects can only be observed if one is able to stick to the diet, which is made difficult by its highly restrictive nature." What's more, there are potential risks for deficiencies of certain minerals (such as calcium thanks to the elimination of dairy) if someone is following a paleo diet for many years.
4. Are there side effects from the diet?
Keto: Yes. Many people get what's called the "keto flu"—experiencing nasty symptoms like brain fog, dizziness, constipation, and exhaustion while their body adjusts to the new way of getting fuel. During the first few weeks on keto, you have to be mindful of your workout schedule and make sure you don't overdo it, as energy levels can suffer in the early stages of keto before you reach ketosis. Another potential keto side effect is dehydration thanks to that initial loss of water weight.
Paleo: Potentially. Paleo diets can backfire when not implemented correctly, says registered dietitian Amy Kubal. "Many people overdo the fats and protein at the expense of vegetables, resulting in lack of fiber and many vitamins, minerals and other nutrients," says Kubal. "I also see more and more people eating 'paleo' processed foods—bars, cookies, bread—and/or baking paleo desserts and breads using alternative flours and sugar sources. These foods are often higher in calories, fat, and sugar than the regular non-paleo versions and can thwart any and all weight-loss efforts."
5. What are the health and body benefits of each diet?
Keto: Keto aficionados swear that the diet helps you lose weight and suppresses your appetite. Plus, one study found that women who practiced resistance training while on the keto diet lost fat but retained more lean muscle than those not following the low-carb diet. Other research suggests following a keto meal plan can help reduce acne.
Paleo: Paleo diets are free of things like additives, preservatives, hormones, and other chemicals—all of which have been linked to a slew of health problems. Research also suggests that paleo can help people who are significantly overweight drop pounds. It may also help improve your cholesterol.
6. Is the eating plan rich in fruits and veggies?
Keto: While veggies such as kale, cucumbers, and asparagus are keto-approved, starchy options such as sweet potatoes and butternut squash aren't allowed because of their high carb content. While some of your usual favorites may have to take a back seat, this opens up the opportunity to diversify your fruits and veggies and choose foods you might not normally go for. (Related: Healthy But High-Carb Foods You Can't Have On the Keto Diet)
Paleo: Most paleo followers stick with seasonal fruit and veg in abundance. Example: This paleo Buddha bowl has six difference veggies in one healthy, high-protein, low-carb recipe.
7. Do you have to buy or follow a specific day-to-day meal plan?
Keto: No. As long as your macros fit the 75/20/5 ratio, you're good.
Paleo: No. You can build your own meal plan and decide your own caloric intake.
8. Is the diet plan easy to follow?
Keto: The keto diet is a serious commitment, and requires a lot of meal planning and willpower, which can make it difficult to sustain. This is exactly why U.S. News & World Report put it at the very bottom of their list of the best and worst diets of 2018.
Paleo: It depends. You will need to plan ahead in order to accurately follow the diet's guidelines, but once you get the hang of what's okay to eat and what's not, it will likely become easier to grasp. To make it a little more flexible, some people choose to follow the 85/15 rule, which is when you follow the paleo rules 85 percent of the time, and allow typically restricted foods in during the other 15 percent.
9. Does the diet work for vegetarians or vegans?
Paleo: It's a little tricky for vegetarians or vegans to try the paleo diet, and some of the same rules can't be applied, says Kubal. The paleo diet is high in plant-based foods, but protein does play a sizable role, too, she adds. For a vegetarian, eggs are still an option, but not for vegans. Vegans would "need to look at incorporating alternate protein sources such as legumes, fermented soy products, and nut- and seed-based proteins," she says, some of which isn't typically allowed on the standard paleo diet plan. "It is difficult to manage for many people and may require some outside help from a registered dietitian to make sure all their nutrition needs are being met." Another option: The "pegan" diet trend that combines elements of the paleo diet and vegan eating.
10. Who shouldn't follow these diets?
If you are looking for a long-term weight loss solution, overarching, sustainable lifestyle changes may be a better choice for you opposed to a time-bound, restrictive diet. "Due to the restrictive nature of both diets, I would not recommend them to pregnant or postpartum women, children or growing teenagers, or anyone who has a history of an eating disorder/disordered eating," says Harbstreet.