Paleo Diet Explained

Diet Review: Paleo Diet for Weight Loss

Paleo Diet Explained

Finding yourself confused by the seemingly endless promotion of weight-loss strategies and diet plans? In this series, we take a look at some popular diets—and review the research behind them.

What Is It?

The Paleolithic or “Paleo” diet seeks to address 21st century ills by revisiting the way humans ate during the Paleolithic era more than 2 million years ago.

Paleo proponents state that because our genetics and anatomy have changed very little since the Stone Age, we should eat foods available during that time to promote good health.

Our predecessors used simple stone tools that were not advanced enough to grow and cultivate plants, so they hunted, fished, and gathered wild plants for food.

If they lived long enough, they were believed to experience less modern-day diseases diabetes, cancer, and heart disease because of a consistent diet of lean meats and plant foods along with a high level of physical activity from intensive hunting. However, the life expectancy of our predecessors was only a fraction of that of people today.

The popularity of the Paleo diet, which hit a peak in 2014, appealed to consumers’ increasing desire to eat more healthfully and to know where their food was coming from. [1]

How It Works

The Paleo diet, also referred to as the caveman or Stone-Age diet, includes lean meats, fish, fruits, vegetables, nuts, and seeds. Proponents of the diet emphasize choosing low-glycemic fruits and vegetables.

There is debate about several aspects of the Paleo diet: what foods actually existed at the time, the variation in diets depending on region (e.g., tropical vs.

Arctic), how modern-day fruits and vegetables bear little resemblance to prehistoric wild versions, and disagreement among Paleo diet enthusiasts on what is included/excluded from the diet. Because of these differences, there is not one “true” Paleo diet.

For example, although white potatoes were recorded as being available during the Paleolithic era, they are usually avoided on the Paleo diet because of their high glycemic index. Processed foods are also technically off limits due to an emphasis on fresh foods, but some Paleo diets allow frozen fruits and vegetables because the freezing process preserves most nutrients.

Overall, the diet is high in protein, moderate in fat (mainly from unsaturated fats), low-moderate in carbohydrate (specifically restricting high glycemic index carbohydrates), high in fiber, and low in sodium and refined sugars. [2] The monounsaturated and polyunsaturated fats (including the omega-3 fats EPA and DHA) come from marine fish, avocado, olive oil, and nuts and seeds.

Grass-fed beef is often highlighted on the diet, which is promoted to contain more omega-3 fats than conventional beef (due to being fed grass instead of grain). It does contain small amounts of alpha-linolenic acid (ALA), a precursor to EPA and DHA. However, only a small proportion of ALA can be converted in the body to long-chain omega-3 fatty acids (EPA and DHA).

The amount of omega-3 is also highly variable depending on the exact feeding regimen and differences in fat metabolism among cattle breeds. [3] In general, the amount of omega-3 in grass-fed beef is much lower than that in oily marine fish.

[3] Cooked salmon contains 1000-2000 mg of EPA/DHA per 3-ounce portion, whereas 3 ounces of grass-fed beef contains about 20-200 mg of ALA.

  • Allowed: Fresh lean meats, fish, shellfish, eggs, nuts, seeds, fruits, vegetables, olive oil, coconut oil, and small amounts of honey. Certain root vegetables sweet potatoes and cassava may be allowed in moderation because of their high nutrient content.
  • Not Allowed: Whole grains, cereals, refined grains and sugars, dairy products, white potatoes, legumes (peanuts, beans, lentils), alcohol, coffee, salt, refined vegetable oils such as canola, and most processed foods in general.
  • Calorie counting and portion sizes are not emphasized. Some plans allow a few “cheat” non-Paleo meals a week, especially when first starting the diet, to improve overall compliance.

The Research So Far

Some randomized controlled trials have shown the Paleo diet to produce greater short-term benefits than diets national nutrition guidelines, including greater weight loss, reduced waist circumference, decreased blood pressure, increased insulin sensitivity, and improved cholesterol. However these studies were of short duration (6 months or less) with a small number of participants (less than 40). [4-6]

One larger randomized controlled trial followed 70 post-menopausal Swedish women with obesity for two years, who were placed on either a Paleo diet or a Nordic Nutrition Recommendations (NNR) diet.

[7] The Paleo diet provided 30% of total calories from protein, 40% fat (from mostly monounsaturated and polyunsaturated fats) and 30% carbohydrates. It included lean meats, fish, eggs, vegetables, fruits, berries, nuts, avocado, and olive oil.

The NNR diet provided less protein and fat but more carbohydrate with 15% protein, 25-30% fat, and 55-60% carbohydrates, including foods similar to the Paleo diet but also low-fat dairy products and high-fiber grains.

Both groups significantly decreased fat mass and weight circumference at 6 and 24 months, with the Paleo diet producing greater fat loss at 6 months but not at 24 months. Triglyceride levels decreased more significantly with the Paleo diet at 6 and 24 months than the NNR diet.

Potential Pitfalls

  • Meal planning. Because the diet relies heavily on fresh foods, expect a time commitment to plan, purchase, prepare, and cook meals. This may be challenging for busy lifestyles or for those less experienced with cooking.
  • Higher cost. Fresh meats, fish, and produce tend to be pricier than processed versions such as frozen or canned.
  • Excluding foods. The exclusion of entire categories of commonly eaten foods whole grains and dairy requires frequent label reading in the supermarket and in restaurants. It may also increase the risk of deficiencies such as calcium, vitamin D, and B vitamins, if these nutrients are not consistently eaten from the allowed foods or a vitamin supplement. For example, there are some nondairy calcium-rich foods that are absorbed well by the body such as collard and turnip greens or canned bone-in sardines and salmon, but you would have to eat five or more servings of these greens and fish bones daily to meet recommended calcium needs. (Note that some greens spinach that are touted to be calcium-rich also contain oxalates and phytates that bind to calcium so very little is actually absorbed.) One small, short-term intervention study of healthy participants showed a 53% decrease from baseline in calcium intake after following a Paleo diet for three weeks. [8] Furthermore, the exclusion of whole grains can result in reduced consumption of beneficial nutrients such as fiber and thus may increase one’s risk for diabetes and heart disease.
  • Health concerns of a high meat intake. Several studies have shown that a high intake of red meat is linked to a higher risk of death, cardiovascular disease, and diabetes.

Unanswered Questions

  • Is there potential for nutrient deficiencies, such as calcium and vitamin D, when following this diet for longer than one year that may make it inappropriate for certain at-risk groups (e.g., those with existing or at high risk of osteopenia or osteoporosis)?
  • Are there long-term negative side effects of omitting entire food groups, especially if the diet is not carefully constructed to include the nutrients from the omitted foods?
  • Is this diet safe and beneficial for everyone (e.g., generally healthy population, higher risk individuals with chronic diseases, elderly)?

Bottom Line

The Paleo diet includes nutrient-dense whole fresh foods and encourages participants to steer away from highly processed foods containing added salt, sugar, and unhealthy fats. However, the omission of whole grains, dairy, and legumes could lead to suboptimal intake of important nutrients.

The restrictive nature of the diet may also make it difficult for people to adhere to such a diet in the long run.  More high-quality studies including randomized controlled trials with follow-up of greater than one year that compare the Paleo diet with other weight-reducing diets are needed to show a direct health benefit of the Paleo diet.

Strong recommendations for the Paleo diet for weight loss cannot be made at this time.

  1. Chang ML, Nowell A. How to make stone soup: Is the “Paleo diet” a missed opportunity for anthropologists?. Evolutionary Anthropology: Issues, News, and Reviews. 2016 Sep;25(5):228-31.
  2. Tarantino G, Citro V, Finelli C.

    Hype or reality: should patients with metabolic syndrome-related NAFLD be on the hunter-gatherer (Paleo) diet to decrease morbidity. J. Gastrointestin. Liver Dis. 2015 Sep 1;24(3):359-68.

  3. Daley CA, Abbott A, Doyle PS, Nader GA, Larson S. A review of fatty acid profiles and antioxidant content in grass-fed and grain-fed beef.

    Nutrition journal. 2010 Dec;9(1):10.

  4. Manheimer EW, van Zuuren EJ, Fedorowicz Z, Pijl H. Paleolithic nutrition for metabolic syndrome: systematic review and meta-analysis, 2. The American journal of clinical nutrition. 2015 Aug 12;102(4):922-32.

  5. Masharani U, Sherchan P, Schloetter M, Stratford S, Xiao A, Sebastian A, Kennedy MN, Frassetto L. Metabolic and physiologic effects from consuming a hunter-gatherer (Paleolithic)-type diet in type 2 diabetes. European journal of clinical nutrition. 2015 Aug;69(8):944.
  6. Obert J, Pearlman M, Obert L, Chapin S.

    Popular weight loss strategies: a review of four weight loss techniques. Current gastroenterology reports. 2017 Dec 1;19(12):61.

  7. Mellberg C, Sandberg S, Ryberg M, Eriksson M, Brage S, Larsson C, Olsson T, Lindahl B. Long-term effects of a Palaeolithic-type diet in obese postmenopausal women: a 2-year randomized trial.

    European journal of clinical nutrition. 2014 Mar;68(3):350.

  8. Österdahl M, Kocturk T, Koochek A, Wändell PE. Effects of a short-term intervention with a paleolithic diet in healthy volunteers. European journal of clinical nutrition. 2008 May;62(5):682.

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The contents of this website are for educational purposes and are not intended to offer personal medical advice.

You should seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.

Never disregard professional medical advice or delay in seeking it because of something you have read on this website. The Nutrition Source does not recommend or endorse any products.

Source: https://www.hsph.harvard.edu/nutritionsource/healthy-weight/diet-reviews/paleo-diet/

Everything You Need to Know About the Paleo Diet

Paleo Diet Explained

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Looking for a new (or a millennia-old) diet strategy? Here's your must-read primer on the paleo diet.

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The paleo diet (also nicknamed the caveman diet, primal diet, Stone Age diet, and hunter-gatherer diet) is hugely popular these days, and goes by one simple question: What would a caveman eat? Here, we explain what the paleo diet involves, its pros and cons, and, ultimately, what a modern person needs to know to decide whether or not to take the paleo diet plunge.

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The paleo diet runs on the same foods our hunter-gather ancestors supposedly ate: fruits, vegetables, meats, seafood, and nuts.

“By following these nutritional guidelines, we put our diet more in line with the evolutionary pressures that shaped our current genetics, which in turn positively influences health and well being,” says Loren Cordain, PhD, professor of health and exercise science at Colorado State University and author of The Paleo Diet.

He says the diet lessens the body's glycemic load, has a healthy ratio of saturated-to-unsaturated fatty acids, increases vitamin and nutrient consumption, and contains an optimal balance of protein, fat, and carbohydrates.

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In fact, the health benefits of the paleo diet are unproven.

“Our ancestors ate this way and didn't have many of the chronic diseases we do, but that doesn't mean the food they ate is the reason why; drawing that conclusion would be saying we live three times longer than our Paleolithic ancestors because we eat fast food,” says Christopher Ochner, MD, research associate at the New York Obesity Nutrition Research Center at St. Luke's and Roosevelt Hospitals. Still, a handful of small studies have tried to determine if a paleo diet is a healthier diet. One small study published in the journal Diabetologia found that the diet improved blood sugar over 12 weeks compared to a Mediterranean one that allowed grains, low-fat dairy, and oils, but it's hard to say whether researchers would come to the same results in a larger study.

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Fresh fruits, fresh vegetables, fresh meat—the paleo diet is all about eating foods straight from the Earth just as our ancestors did.

Those ancestors didn't have livestock or crops to call their own, so Cordain advises to go with grass-fed and organic varieties whenever possible to limit exposure to pesticides, antibiotics, and other chemicals that didn't exist back then.

Research from Emory University suggests that Paleolithic people obtained about 35% of their calories from fats, 35% from carbohydrates, and 30% from protein.

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One of the biggest pluses of the paleo diet isn't about nutrition at all—it's about the support paleo eaters give each other. Online community forums, pages, and even Meetup groups are filled with people living the ancient lifestyle in modern times. You won't find that with many other diets.

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Anything that comes in a box, jar, or bag should be avoided on the paleo diet—as should anything that just wasn't consumed back then. That means no grains, dairy, added salt, or legumes (including peanuts, beans, lentils, and soybeans), according to Robb Wolf, a former research biochemist, paleo expert, and author of The Paleo Solution.

While potatoes are generally outlawed on the diet, Wolff says they are okay to eat sparingly as long as you earn them through exercise (more on that next). Alcohol and honey are also generally considered paleo no-nos, but red wine tends to be the closest option there is to a paleo drink, and honey is far preferred to table sugar or artificial sweeteners.

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“The paleo diet is by no means a temporary diet,” says Cordain. It's meant to be a lifestyle, just as it was thousands of years ago. You don't just stop it if and when you start feeling better or reach your goal weight—you stick it out for the long haul.

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Exercise is a vital part of the live-by-your-genetic-code equation. Surviving in the Stone Age meant a constant on-the-go lifestyle that probably required 4,000-plus calories a day, according to David L.

Katz, MD, director of the Yale University Prevention Research Center.

Even most people who hit the gym regularly won't need to eat that many calories, but the principle of using food as fuel to exercise still stands.

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While the diet as a whole hasn't been well studied, the benefits of cutting packaged foods from your diet could be huge.

According to the Harvard School of Public Health, three quarters of the average American's sodium intake (which is almost double what it should be!) comes from commercially prepared foods.

And, one Public Health Nutrition study found that people who cook at least five times a week are 47% more ly to be alive 10 years later compared to those who rely more on processed foods.

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Our ancestors didn't chase cows and chickens around in the wild. They hunted game, antelopes, buffalo, and probably some animals we've never heard of that are long extinct.

Their meat was generally quite lean, and provided more healthy omega 3s than meats from modern day animals, even the grass-fed ones, according to Dr. Katz.

Many of the plants that thrived back then are also extinct today, making it impossible to truly follow their meal plan, he says.

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Experts estimate that our ancestors consumed a one-to-one ratio of calories from meats to produce. Since you have to eat a lot of salad to consume the same amount of calories in a steak, the paleo diet should ideally include mostly fruits and vegetables, Katz says.

However, many people don't realize that and eat too much meat. Consuming excess protein and not enough carbs can cause kidney damage and also increase your risk of osteoporosis, Dr. Ochner says.

Plus, since most of today's meats are higher in saturated fat than those of yesteryear, it can increase the risk of heart disease, Dr. Katz says.

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“Every fad diet thinks it has discovered the root of all evil,” says Dr. Ochner.

But nutrients in legumes, whole grains, and dairy—all of which are forbidden on the paleo diet—can help to lower the risk of osteoporosis and cardiovascular disease, reduce blood pressure, and promote a healthy weight, he says.

Cutting dairy, the primary source of calcium and vitamin D in modern diets, is especially worrisome for women who want to avoid osteoporosis.

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Paleo eating requires a lot of planning, prep time, and mental resolve. For instance, eating out on the diet isn't as simple as ordering chicken and a salad.

Think: In what oil was the chicken cooked? Did any of the salad toppings come processed, canned, or packaged? “As with every elimination diet, it's just not doable long term,” Dr. Ochner says. While weight loss is far from the sole purpose of eating paleo, going on and off of the diet can lead to big weight swings.

Any yo-yo diet starts in weight loss from both muscle and fat, and usually ends with weight gain of all fat, which contributes to a slower metabolism and increased insulin resistance.

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Following the paleo diet can be pricey.

Inexpensive and healthy non-meat protein sources soy and beans are off-limits, and a recent BMJ Open study shows that healthy meats lean ground beef and boneless, skinless chicken breasts cost an average of 29 cents more per serving compared to less-healthy ones, such as high-fat ground beef and chicken drumsticks. Even switching from peanut butter to paleo-approved almond butter will cost you—it goes for up to $13 a jar.

Source: https://www.health.com/nutrition/everything-you-need-to-know-about-the-paleo-diet

Paleo diet: A guide and 7-day meal plan

Paleo Diet Explained

The paleo diet is an eating plan that mimics how prehistoric humans may have eaten. It involves eating whole foods that people could theoretically hunt or gather.

Advocates of the paleo diet reject modern diets that are full of processed foods. They believe that returning to how hunter-gatherers ate may cause fewer health problems.

The paleo diet is not safe for everyone. Doctors do not know its effects on children, pregnant women, or older adults. People with chronic conditions, such as inflammatory bowel disease, should also speak to a doctor before trying a paleo diet.

This article explores paleo principles and provides a 7-day paleo diet meal plan to follow. Read on to learn how to eat our ancestors.

Share on PinterestPeople who support the paleo diet claim that it can aid weight loss and reduce the risk of some health conditions.

The focus of the paleo diet is on eating foods that might have been available in the Paleolithic era. The paleo diet is also known as the stone age diet, hunter-gatherer diet, or caveman diet.

Before modern agriculture developed around 10,000 years ago, people typically ate foods that they could hunt or gather, such as fish, lean meats, fruits, vegetables, nuts, and seeds.

The development of modern farming changed how people ate. Dairy products, legumes, and grains became part of people’s diets.

Proponents of the paleo diet believe that the human body has not evolved to process dairy, legumes, and grains and that eating these foods could increase the risk of certain health conditions, such as heart disease, obesity, and diabetes.

Foods that a person can eat on the paleo diet include:

  • vegetables
  • fruit
  • nuts
  • seeds
  • lean meat
  • fish
  • eggs
  • herbs
  • spices
  • oils that come from fruit or nuts, such as olive oil, coconut oil, and almond oil

People following a paleo diet tend to choose grass-fed, organic meats because these are the least processed.

Foods to avoid on the paleo diet include:

  • grains, including wheat, oats, and barley
  • legumes, such as beans, lentils, peas, and peanuts
  • dairy
  • trans fats (hydrogenated oils)
  • refined sugars
  • artificial sweeteners
  • low-fat or diet products
  • salt

People following the paleo diet should drink lots of water. Some people on this diet also drink black coffee or green tea, but they avoid all soft drinks and juices with added sugar.

Getting regular exercise is another vital part of the paleo lifestyle.

We have created a 7-day paleo diet meal plan with the intention of providing a guide for people who want to try this way of eating.

People can make changes to each meal according to their personal preference. Fruits, nuts, and seeds make excellent snacks or desserts.

Day 1

On the first day, a person could eat the following:

  • Breakfast: Avocado, kale, banana, and apple smoothie with almond milk.
  • Lunch: Mixed salad leaves with fried seabass, pumpkin seeds, and an olive oil dressing.
  • Dinner: Roast chicken with a stuffing of onions, carrots, and rosemary.

Day 2

On the second day, use the leftovers for lunch and enjoy fish for dinner:

  • Breakfast: Scrambled eggs with wilted spinach, grilled tomatoes, and pumpkin seeds.
  • Lunch: Mixed salad leaves with leftover roast chicken and an olive oil dressing.
  • Dinner: Oven-baked salmon with asparagus and broccoli fried in coconut oil.

Day 3

On day 3, use any leftover salmon from the previous day:

  • Breakfast: Chopped bananas with blueberries and almonds.
  • Lunch: Mixed salad leaves with leftover salmon and an olive oil dressing.
  • Dinner: Beef stir-fry with mixed peppers, using coconut oil to fry.

Day 4

On the fourth day, start with a protein-packed egg:

  • Breakfast: Broccoli fried in coconut oil with toasted almonds and a poached egg.
  • Lunch: Mixed salad with tuna, boiled eggs, seeds, and olive oil.
  • Dinner: Harissa-baked chicken wings with steamed broccoli.

Day 5

On day 5, a person could prepare the following:

  • Breakfast: Coconut milk, mixed berries, and spinach smoothie.
  • Lunch: Butternut squash, broccoli, and tomato omelet with mixed salad.
  • Dinner: Red pepper, broccoli, baby corn, and salmon stir-fry.

Day 6

On the sixth day, start with a savoury breakfast:

  • Breakfast: Bacon, eggs, and tomatoes fried in olive oil.
  • Lunch: Mixed vegetable and chicken soup with turmeric.
  • Dinner: Grilled lamb chops with wilted spinach and spiced red cabbage.

Day 7

On day 7, add healthful fats by using avocado:

  • Breakfast: Spring onion, tomato, and mushroom omelet.
  • Lunch: Mixed salad with chicken, avocado, seeds, and olive oil.
  • Dinner: Slow-cooked beef stew with mixed vegetables.

People claim that the paleo diet offers many health benefits, which include promoting weight loss, reducing the risk of diabetes, and lowering blood pressure.

In this section, we look at the scientific evidence to see whether research supports any of these claims:

Weight loss

An older 2008 study found that 14 healthy volunteers achieved an average weight loss of 2.3 kilograms by following the paleo diet for 3 weeks.

In 2009, researchers compared the effects of the paleo diet with a diet for diabetes on 13 people with type 2 diabetes. The small study found that eating the paleo way reduced participants’ body weight and waist circumference.

A 2014 study of 70 postmenopausal women with obesity found that following a paleo diet helped participants lose weight after 6 months.

However, after 2 years, there was no difference in weight loss between participants following the paleo diet and those adhering to regular Nordic nutrition recommendations. These results suggest that other healthful diets may be just as successful at promoting weight loss.

The authors of a 2017 review noted that the paleo diet helped reduce weight in the short term but concluded that this result is due to caloric restriction, or consuming fewer calories.

Overall, the research suggests that the paleo diet may help people lose weight initially but that other diets that reduce calorie intake may be just as effective.

More research is necessary before doctors recommend the paleo diet for weight loss. Currently, doctors advise people to follow a calorie-controlled diet and exercise more to lose weight.

Reducing diabetes risk

Will following a paleo eating plan reduce a person’s risk of developing diabetes? The results of some initial studies are promising.

Insulin resistance is a risk factor for diabetes. Improving a person’s insulin sensitivity decreases the lihood that they will develop diabetes and can help those who have diabetes reduce their symptoms.

A small study in 2015 compared the effects of the paleo diet with those of a diet recommendations from the American Diabetes Association on people with type 2 diabetes.

While both diets improved the participants’ metabolic health, the paleo diet was better at improving insulin resistance and blood sugar control.

An older 2009 study of nine sedentary volunteers without obesity also found that the paleo diet improved insulin sensitivity.

There is a need for more recent research on the paleo diet and diabetes, but the evidence to date suggests that eating a hunter-gatherer may improve insulin sensitivity.

Lowering blood pressure

Share on PinterestResearch into the impact of the paleo diet on blood pressure is ongoing.

High blood pressure is a risk factor for heart disease. Some people think that the paleo diet can help keep blood pressure in check and promote heart health.

An older 2008 study of 14 healthy volunteers found that following the paleo diet for 3 weeks improved systolic blood pressure. It also decreased weight and body mass index (BMI). The study did not include a control group, however, so the results are not conclusive.

A 2014 study supported these early findings. Researchers compared the effects of the paleo diet with those of a diet that the Dutch Health Council recommend on 34 participants with characteristics of metabolic syndrome, a condition that increases the risk of heart disease.

Results showed that the paleo diet reduced blood pressure and blood lipid profile, both of which can improve heart health.

Although initial studies suggest that the paleo diet may reduce blood pressure and support heart health, more recent and extensive studies are necessary to make any conclusions.

Followers of the paleo diet aim to eat in the way that our prehistoric ancestors did. They seek out whole, unprocessed foods and avoid processed foods, grains, legumes, and dairy.

Paleo advocates argue that our bodies are unable to process foods that emerged after the development of farming.

A paleo meal plan may support weight loss, improve insulin sensitivity, and reduce blood pressure in the short term. The results of small, initial studies support some of these health effects, but more research is necessary to confirm them.

The paleo diet may not be safe for everyone, so it is best to speak to a doctor or dietitian before making significant dietary changes.

For people who are interested in trying the paleo diet, the 7-day meal plan above is a good place to start.

Source: https://www.medicalnewstoday.com/articles/324405

Paleo Leap

Paleo Diet Explained

Source: https://paleoleap.com/paleo-101/