Paleo diet side effects

The paleo diet, like any significant dietary change, can lead to side effects as the body adapts to a new way of eating.

When going on a paleo diet you have to exclude certain food groups, and this combined with a lower carbohydrate intake can take time for the body to get used to. This can result in any of the following side effects:

  • Low blood sugar (hypoglycemia) – if taking certain glucose lowering medications
  • Low-carb flu
  • Cravings
  • Lack of energy initially
  • Bad breath
  • Change in bowel habits

These side effects are usually temporary and can be minimised by taking certain precautions.

It is important to speak with your doctor before adopting the paleo diet, and you should consult them if you think any side effects you are experiencing are abnormal or have been going on for too long.

Low blood sugar (hypoglycemia)

It is important to take precautions before adopting the paleo diet if you use insulin or other drugs, such as sulphonylureas or glinides , which can cause hypoglycemia.

Eating low-carb means you’ll require less medication, and your dosages may need to be altered to prevent low blood sugar This is one of the main reasons why it’s important to consult your doctor before starting a paleo diet.

Low-carb flu

Because most paleo foods are relatively low-carb, there is often lower demand on the pancreas to produce insulin

Research has shown the paleo diet can decrease insulin secretion and therefore improve the effectiveness of insulin This reduces insulin resistance , the driving force of type 2 diabetes , and may allow some people to reduce the amount of medication needed.

Improved heart health

Low-carb flu is one of the most commonly-reported side effects of the paleo diet. Symptoms can include headaches, fatigue , weakness, hazy thinking (brain fog) and irritability, which can result from reducing carbohydrate intake.

For somen, low-carb flu can take days to subside, but for others it can take a couple of weeks. Some may not even experience these symptoms are at all.

Lowering your carb intake gradually can help to ease the transition into the paleo diet and lower the severity of low-carb flu.

More energy

Eating foods low on the Glycemic Index (GI) as part of a paleo diet means you will avoid the drop in energy that normally occurs shortly after high GI and sugary foods.

For somen, low-carb flu can take days to subside, but for others it can take a couple of weeks. Some may not even experience these symptoms are at all.

Lowering your carb intake gradually can help to ease the transition into the paleo diet and lower the severity of low-carb flu.


People can struggle with food cravings early on in the diet, but this shouldn’t last long.

Significantly, studies have shown that eating a diet based on lean meat, fish, fruits and vegetables is more satiating than a high-carb, low-fat diet recommended by the NHS

Lack of energy

A reduction in carbohydrate might lead to the body entering into ketosis , a state in which the body gets its energy from burning body fat. As the body switches into ketosis and adapts to this way of using energy, it can lead to a temporary feeling of lethargy. This effect may or may not occur depending on how low your carbohydrate intake goes.

Energy levels will usually return before too long and many people report having subsequently increased physical energy and mental clarity.

Bad breath

Some people may find that their paleo diet leads to bad breath. This varies from one person to another and may depend on individual food choices, diet composition and other circumstances.

One cause of bad breath is going into ketosis. Ketones , which can exhaled on the breath, may sometimes be unpleasant. Again, the effects of ketones on the breath can vary depending on the individual and circumstances.

Another possible reason for bad breath can be increased protein intake, which results in the gut producing hydrogen sulphide as part of digestion. This can lead to what are known as sulphur burps, which can have an eggy smell.

Bad breath is usually temporary and will disappear after a few weeks once your body has adapted to the paleo diet. If, however, it is causing you discomfort, try brushing your teeth more frequently throughout the day. You could also try using sugar-free chewing gum.

Change in bowel habits

A change in the type of foods you eat may also require the gut to adapt, which can result in a change in bowel habits.

Any initial bowel discomfort will usually be temporary and resolve as soon as the gut adapts to eating different foods.

Some people may find that their bowel health improves and movements become more consistent on a paleo diet.

5 Hidden Dangers of the Paleo Diet

The Paleo Diet – commonly known as the Caveman Diet – traces back millions of years to the era of early humans. After a recent comeback, it’s considered a common fad in current diet culture.

The basic premise: we should eat how we’ve been biologically and genetically programmed. If our ancestors thrived on the food they hunted and gathered – high fat, animal protein, seafood and vegetables, for instance – we should too. And since they weren’t subject to today’s more diverse options – processed food, grains, carbohydrates, dairy products, salt, vegetable oil and refined sugar (among others) – then we should avoid those food groups as well.

While some studies link weight loss and overall health improvements when following the Paleo Diet, many remain skeptical regarding its overall effectiveness. From a nutritional standpoint, adhering to certain parts of this diet can result in potentially damaging consequences. Here are five hidden dangers to consider:

1). Low to moderate carbohydrate intake.

Hidden danger: Paleo calls for the exclusion of cereal grains – wheat, rye, barley, oats, corn and brown rice, to name a few. These are great sources of fiber, B vitamins, iron, magnesium and selenium. Grains help our bodies control blood sugar, lower cholesterol and fight the risk of chronic diseases. Consistent low carbohydrate intake may lead to an overuse of fat for energy, also known as ketosis. Ketosis occurs when by-products of fat breakdown, called ketones, build up in the bloodstream. High levels of ketones can lead to dehydration and eventually coma due to severe metabolic abnormalities.

Furthermore, following a low to moderate carbohydrate diet can make exercise a physical battle for those following the Paleo diet. During aerobic exercise (longer exercises such as running, biking, swimming and walking), our bodies use carbohydrates for fuel. Without adequate carbohydrates in the diet, our body turns to both body fat and muscle for energy. This results in the breaking down of muscle mass, which is known to increase our metabolism and help us burn more calories per day. Feelings of physical fatigue and exhaustion, throughout the day and during exercise, can be signs of muscle breakdown.

2). Restriction of dairy products

Hidden danger: Dairy restriction can lead to deficiencies in calcium and vitamin D, which are critical to bone health.

3). Saturated fats are suggested in very generous amounts

Hidden danger: Consuming the Paleo Diet-recommended amount of saturated fats can increase the risk of kidney and heart disease, as well as certain cancers.

4). High intake of red meat and high fat meat

Hidden danger: Past and current research suggests that a heightened level of high fat meat and saturated fat can increase LDL (bad cholesterol) and the risk of bowel cancer. Per the American Heart Association, an adult should consume a total of ~13 grams of saturated fat per day. On a Paleo diet, saturated fat intake can approach upwards of 50 grams per day.

5). Segmentation of “good” and “bad” foods

Hidden danger: A one-size-fits-all “best diet” approach does not work and can be problematic to most individuals, especially those prone to black and white / all-or-nothing thinking. Categorizing foods into “good” and “bad” can lead to feelings of guilt, shame and low self-worth when the “rules” of a diet are broken.

In the end, eating like our ancestors isn’t required to live a healthy lifestyle; in fact, it could even cause adverse effects (as clearly shown above). While those living millions of years ago may have gotten by on this diet, evolution has altered our genetic makeup and how we digest food.

If you are interested in changing your eating habits, what’s most important is making sure your health background and nutritional requirements are considered. A professional dietitian can help to ensure the most appropriate plan for you and your unique lifestyle.

Bridget Hastings Komosky MS, RD, CD-N is a Registered Dietitian Nutritionist. She completed her Bachelor of Science degree in Nutrition at Ithaca College and her Master of Science degree in Clinical Nutrition at New York University. She completed her dietetic internship at NewYork-Presbyterian Hospital in New York, NY. Her work in eating disorders includes a six month fellowship at NewYork- Presbyterian Hospital and New York Psychiatric Institute, employment as a dietitian on the inpatient eating disorder unit at NewYork-Presbyterian Hospital, and now as a dietitian at Walden Behavioral Care since October 2013. Currently at Walden, Bridget works with the adult and adolescent Partial Hospitalization Programs and the Binge Eating Disorder Intensive Outpatient Program. She also has a private practice.

*This blog post does not necessarily represent the views of Walden and its management. The Walden Blog is meant to represent a broad variety of opinions relating to eating disorders and their treatment. Comments are welcome, but respect for the opinions of others is encouraged.

Is the paleo diet safe for your health?

FEATURE | Posted June 10, 2015

UC Davis Health dietitian weighs in on latest food fad

Alex Nella selects redbor kale, Swiss chard and curly green kale — some of his favorite “super foods” — from UC Davis Health’s weekly farmers market. Nella counsels children and their families on healthy eating as the lead dietitian in pediatric specialty clinics. He also offers food-choice tips to faculty, staff and students in the UC Living Fit Forever wellness program.

The popular Paleolithic diet (also known as the paleo, caveman, Stone Age or steak and bacon diet) centers on the idea that eating like our original ancestors is aligned with our genetics and therefore optimal for good health. A paleo dieter’s food choices are limited to what in prehistoric times could be hunted, fished or gathered such as meats, fish and vegetables. The underlying theory is that the rise in chronic diseases in modern society stems from the agricultural revolution, which added grains, legumes and dairy to meals, leading to a host of chronic diseases and conditions — from obesity to allergies.

But is the paleo diet safe? UC Davis Health dietitian Alex Nella discusses the pros and the cons of the food fad.

Can we assume that cave people ate mostly meat?

Not really. People living in the Paleolithic period, or “cave people,” ate whatever their surroundings afforded them. When surrounded by fish or marine animals, that’s what they ate. In tropical habitats, they ate a variety of plant and animal foods. In certain environments, the majority of calories may have come from protein, but the bulk of the diet was still plants. So calling a diet that consists mostly of protein the “paleo diet” isn’t accurate.

Is the paleo healthy?

It has the potential to be healthy. The typical paleo diet, however, puts most at risk for deficiencies in calcium and vitamin D, which are critical to bone health. At the same time, saturated fat and protein can be consumed far above recommended levels, increasing the risk of kidney and heart disease and certain cancers.

But shouldn’t we reduce carbohydrates and dairy in our diets?

Not true for complex carbohydrates. Whole grains, fruits and vegetables are important fuels for brain and muscle activity. But most of us can and should eat fewer refined carbohydrates, which add unnecessary ingredients and calories but little fiber and protein and few vitamins and minerals to our diets. They also are often fortified just to appear healthy on nutrition labels.

Dairy is an individual choice. But if it’s significantly limited and not replaced with alternative food sources of calcium, supplements of calcium and vitamin D may be necessary. Paleo advocates often say dairy promotes inflammation, but some research shows the opposite: low-fat dairy intake actually decreases inflammatory markers in the blood.

What do you like about the paleo diet?

It is high in fiber, potassium and antioxidants while being low in simple carbohydrates, sodium and sugar. It emphasizes local, sustainable, organic and non-GMO foods and grass-fed meat options. It discourages foods that are processed or have artificial ingredients and colorings. It encourages foods that make the body work hard to obtain calories while providing nutrients that optimize efficient use of those calories. It may kick-start weight loss and, at least in the short-term, improve blood sugar and lipid profiles.

A good resource for achieving dietary balance is from the U.S. Department of Agriculture.

What are the major downsides?

The paleo isn’t effective for sustained weight loss, as it is very difficult to stay committed to any diet that is too restrictive of one or more food categories. In terms of overall health, it could over time increase lipids like total and LDL (low-density lipoprotein, or “bad”) cholesterol that raise the risk of heart disease. Not getting enough calcium increases the risk of osteoporosis, rickets and bone fractures. Chronically low carbohydrate intake may lead to an overuse of fat for energy, or ketosis. Medical supervision is recommended for those on the paleo diet, especially for anyone with heart, kidney, liver or pancreatic disease or who is interested in maintaining the very low-carbohydrate version of the diet.

What do you tell people who ask about the paleo diet?

I encourage them to use the paleo as the starting point of a healthy diet but to add beans, lentils, nuts, whole grains, and low-fat or nonfat dairy or other calcium sources such as dark leafy greens, tofu, and soy or almond milk. I also recommend that they carefully choose protein sources, emphasizing quality over quantity. Plate balance is the key. Good resources for achieving that balance are the recommendations from the U.S. Department of Agriculture, the DASH (dietary approaches to stop hypertension) eating plan from the National Institutes of Health, or guidance from a dietitian.

If you haven’t heard about the paleo diet by now, you must be living in a cave—ironically, the very place this prehistoric meal plan supposedly originated. “The idea is based on eating like your ancestors ate,” says Lisa Young, R.D. author of The Portion Teller Plan. “Very often, you’re going high protein, lower carb, and cutting out dairy and sugar.” In other words, eat like a caveman.

Paleo isn’t without its pros: You’re cutting out a ton of processed foods and the higher protein-to-carb ratio can leave you satisfied with smaller portions, helping with weight loss. But, says Young, “it’s totally not sustainable. Whenever you cut out entire food groups, you’re not going to be able to live with it for a long time.” Plus, she points out, paleo advocates also restrict a lot of healthy plant-based proteins including beans and legumes, some whole grains, and low-fat dairy—all foods that have been shown to help with weight loss.

Ultimately, Young says, paleo dieting can be a good way to jumpstart a more whole-foods approach to your diet and eliminate processed junk food and sugar. Just don’t go caveman crazy. It’s okay—more than that, good for you—to have beans, legumes, whole grains, starches, and some low-fat dairy in your diet.

But even paleo devotees who do achieve the loincloth-ready bodies of their dreams may have other side effects to contend with. For instance:

Christine Frapech

“When you go on a lower-carb diet, very often you can get lightheaded and dizzy because you need carbs for energy,” says Young. The resulting fatigue, lethargy, and irritability are so well-known by nutrition pros that the initial adjustment period has become known as “low-carb flu.”

Related: 3 Signs You Need To Start Eating More Carbs

Christine Frapech

When you’re dieting, that’s a good thing, right? Yes and no. “Going too low-carb can eventually send your body into starvation mode,” says Young. That can have a host of negative side effects as your body tries to conserve energy. It may also decrease thyroid function as a result.

Watch a hot doc explain what to do about a thyroid disorder:

​ Christine Frapech

Without carbs to torch for energy, your body shifts its focus to fat burning, or ketosis. Sounds good, but, says Young, “the process generates compounds that make your breath smell,” namely acetone.

Related: ‘I Lost 70 Pounds Without Giving Up Carbs Or Joining A Gym’

Christine Frapech

When you eat a diet high in animal fat, you’re bound to up your saturated fat intake and that impacts your cholesterol. “’Have all the meat you want’ is not a great message as far as I’m concerned,” says Young. (Learn how bone broth can help you lose weight with Women’s Health’s Bone Broth Diet.)

Christine Frapech

Eating a lot of fat can grease the skids of your digestive tract. “Getting some starches and carbs in your diet helps keep things cohesive,” says Young. That’s a polite way of saying that paleo can make you poop.

The paleo diet has been getting more attention over the past years. This approach mainly encourages people to eat like the human ancestors, who loved high protein foods.

To date, the paleo diet is a high-protein, low-carbohydrate plan mainly used for weight loss. It encourages people to avoid processed foods, including dairy products and those high in sugar.

The main advantage of eating more protein is it helps people feel full faster even after eating small meals. However, paleo also comes with some problems.

“It’s totally not sustainable,” Lisa Young, author of “The Portion Teller Plan,” said. “Whenever you cut out entire food groups, you’re not going to be able to live with it for a long time.”

The diet limits the consumption of low-fat dairy and important plant-based proteins, including whole grains, beans and legumes. These foods are known for providing a number of health benefits and supporting weight loss.

The people on the paleo diet are at risk of the “low-carb flu.” This condition occurs when the body loses carbs that are important for energy generation, according to Women’s Health.

Low-carb flu could stay from days to weeks, causing headaches, fatigue, weakness, hazy thinking and irritability.

“When you go on a lower-carb diet, very often you can get lightheaded and dizzy because you need carbs for energy,” Young said. “Going too low-carb can eventually send your body into starvation mode.”

But low-carb flu is just one of the many negative effects of the paleo diet. This article explores other unwanted changes that may occur when you transition to the high-protein weight loss plan.

Side Effects of Paleo Diet

Low Energy

A sudden decrease in carbs could trigger ketosis in the body. In this state, body fat is used to produce energy. However, ketosis can cause lethargy and lead to faster decline in energy levels.

Affects Gut Health

The paleo diet forces the gut to adapt to a new set of foods to support bodily functions. But the transition could also trigger changes in bowel habits.

In most cases, paleo causes bowel discomfort in people. However, some reported improved bowel health and movements.


To those people who take insulin or other drugs, like sulphonylureas and glinides, for their conditions, moving to the paleo diet may increase the risk of hypoglycemia or very low blood sugar, according to

It is because of lower carb intake. The paleo diet may require changing your dosages to maintain blood sugar levels.

Bad Breath

Bad breath is another common side effect of paleo diet. Experts said it may be because of ketosis or the increased protein intake, which causes sulphur burps with an eggy smell.

Luckily, it could be easy to reduce the bad effects of the high-protein diet. Simple meal changes and adding healthy food choices could help improve health and avoid problems.

Doctors can help guide you in the transition by identifying potential side effects and the nutritional needs of your body.

© The paleo diet mainly encourages people to eat like the human ancestors, who loved high protein foods.

Are There Any Long Term Side Effects of a Paleo Diet?

Jeremy Hendon | July 16

Besides living longer and feeling better?


I really want to give a 100% definitive answer to this question, but I don’t think that would be fair.

Long-Term Clinical Trials

They don’t exist.

Not for Paleo. Not yet, anyway.
But then again, there are no real long-term clinical trials of a typical diet filled with processed junk food.

My point is that it’s actually incredibly hard to run long-term studies on any type of diet. Most “studies” are simply observations of large groups of people, and those observations don’t really prove or disprove any potential side effects.

The Non-Scientific Side Effects

If we’re not relying solely on science, then my tongue-in-cheek answer would be that the only known side effects are looking and feeling much better, having a lot more energy, and curing many illnesses.

One of the reasons, though, that I wouldn’t completely rule out any side effects is because even a Paleo diet differs from one person to another. Just like one vegetarian might eat only on ramen noodles and pizza while another might eat only fruits and vegetables.

If you’re eating a super-clean, completely pastured and organic, low-sugar version of Paleo, then that will be different from eating foods that are packaged and sold as “Paleo.”

In the end, we do have over 2 million years of observational data that tells us that Paleo diets didn’t seem to have many side effects, and I think that’s a pretty good place to start.

Images: Copyright (c) iko from Fotolia and Carla Nichiata from Fotolia

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 like 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.

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. 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. In general, the amount of omega-3 in grass-fed beef is much lower than that in oily marine fish. 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.

The following is a summary of foods generally permitted on the diet:

  • Allowed: Fresh lean meats, fish, shellfish, eggs, nuts, seeds, fruits, vegetables, olive oil, coconut oil, and small amounts of honey. Certain root vegetables like 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 based on 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).

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. 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 like 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 like 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. 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.


  • Healthy Weight
  • The Best Diet: Quality Counts
  • Healthy Dietary Styles
  • Other Diet Reviews
  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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What Is the Paleo Diet?

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By eating a diet of meat, seafood, fruits and vegetables—foods that were most abundantly available to our hunter-gatherer ancestors—people can not only lose weight but also cut their risk of cardiovascular disease and other chronic conditions through restriction of dietary choices. This diet may be considered the ultimate in “back to basics,” because it bars foods that became popular with agricultural advancements—namely, all grains, refined or processed foods, salt, trans fats and high-glycemic carbohydrates.
How It Works
Carbohydrates are believed by some to cause inflammation in the body, so by restricting this food group and consuming only nutrient-dense protein and produce, individuals are thought to stave off weight gain, heart problems, diabetes and other conditions.
This diet is popular among people trying to build muscle, because it allows for all the protein you want. People following the paleo lifestyle can eat their fill of shellfish, eggs, tree nuts, meat, vegetables, roots, berries and fruit. Strictly excluded from this diet are dairy, grains, sugar, legumes, processed fats, added salt and anything that people wouldn’t have recognized as food hundreds of years ago. Additionally, individuals on this diet can drink only water, green tea or coconut water.

Success Rate
The paleo diet is still pretty new, so there’s not much research on the long-term success rates. However, one small study on nine individuals who consumed the paleo diet for 10 days showed that the dieters experienced better insulin response, glucose levels and lipid profiles after the trial period.
Health Pros and Cons
Pros are that it includes an abundance of produce and omega-3 fats, both of which are thought to benefit many areas of wellness. High protein intake may also mean that dieters will be less hungry on this plan compared to others.

The cons of the paleo diet, according to experts, are that it cuts out traditionally healthy foods like low-fat dairy, legumes and whole grains. These are thought to provide much of the calcium, vitamin D, fiber and other nutrients in many American diets.
How Easy Is It?
Some paleo plans are more restrictive than others, so it depends on the one you choose, as well as your natural proclivity toward certain foods. Some experts say it’s fine to eat raw honey or coconut palm sugar in moderation. Others might instruct dieters to fast, consume only raw foods or eliminate nightshade vegetables like eggplant and tomatoes. One benefit to the diet’s popularity is that there are plenty of recipes out there that make it easier for people to follow the plan.

Who Is It Best For?
Active individuals looking to gain muscle and lose fat may stand to benefit the most from this diet. In general, it’s not recommended for vegans or vegetarians because it’s so heavy in meat and restricts plant sources of protein like legumes and whole grains.

Costs and Special Products
Considering the relatively high costs of fresh produce and healthy meats, this diet may require some budgeting. But, there are no special products to buy.

The Paleo Diet Review

  • No exercise plan is needed
  • Cons of The Paleo Diet

    • Highly restrictive and eliminates many favorite foods such as pasta, bread, potatoes and desserts.
    • Recent research has shown that eating Paleo style could have negative effects on heart health
    • May be socially disruptive; difficult to eat out or at social occasions plus is not family friendly.
    • May be an initial withdrawal period when dieters commence the diet due to eliminating coffee, sugar, alcohol and refined carbohydrates.
    • Diet is based on speculation to some degree, as it is impossible to be certain what exactly our Paleolithic ancestors ate.
    • Will require careful planning to ensure that calcium is adequately supplied due to the absence of dairy products.
    • Not suitable for vegans or vegetarians.

    Do I Need to Exercise?

    Although some books on the Paleo Diet may include an exercise regime, the general scope of this diet does not include a specific exercise plan.

    WLR Verdict

    Since the Paleo diet involves cutting down on processed foods it is certainly a good way to ditch the junk. The Caveman Diet bans booze, high-fat, calorific processed foods and refined carbs (although diet fizzy drinks are allowed).

    It encourages you to eat more good-quality protein such as lean meat, chicken and fish, which helps to keep you fuller for longer. Eating more fruit, veg and nuts is a good way to boost fibre and to help fill you up and to increase intake of vitamins, minerals and antioxidants.

    However, there are several concerns with the Paleo Diet. Because dairy products are eliminated, intakes of bone-building calcium are likely to be low, and a lack of recommended exercise will not help tone and strengthen your body.

    Many people who embark on the Paleo Diet do feel drained initially because they cut back on carbs and rely on fats and protein as a source of energy. Combined with reports of bad breath, headaches and irritability you really need to be sure that this diet is for you.

    Like all drastic changes in diets and lifestyle, if you do decide to go ahead with the Paleo Diet, ease yourself into it slowly. As with similar eating plans, no extreme is the right way to go, so your approach should be to modify and change depending upon your needs and lifestyle.

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