Top 5 Diet Plans: Pros & Cons

I was recently placing a Thrive Market order and noticed that you can narrow your search by “shop by diet”. I personally don’t follow any specific diet plan, but I was curious the options they offered. There are a lot of diet options (which I think is great for people who do have specific dietary needs), but it got me thinking how overwhelming this might feel for some.

As a Registered Dietitian, I did not learn about many of these eating styles in school and it’s my job to stay on top of the emerging science and research behind these new eating styles and trends. I think too often many people blindly start a new diet with hopes that this will answer all of their health issues without really knowing the specifics of what the entails.

I thought today it might be helpful for some if I reviewed what I consider the top 5 diet plans. I will highlight the basics about what the diet is and a review a handful of pros and cons. I’m not able to do a deep dive into every diet, so I encourage you to also do your own research if you’re considering adopting a new diet plan. As always, if you have any medical conditions it’s always best to speak with you doctor before making a big dietary change.

KETOGENIC (keto) DIET: This is essentially a very low-carb diet. A ketogenic diet primarily consists of high fat, moderate protein, and very low carbohydrate intake, but this diet does not restrict overall caloric intake. This diet is prescribed to manage certain medical conditions like epilepsy, but can also be a significant tool for weight loss. Here is how it works…carbohydrates are the bodies primary source of energy, so when you limit that easy energy source to 20-50 grams of carbohydrates a day your body eventually runs out of fuel, glycogen stores are depleted, and metabolic changes will occur. One of those changes is that by day 3-4 of eating very low carb your body will go into “ketosis” meaning you’ll start to break down protein and fat for energy, which can make you lose weight.

Pros: Their is scientific evidence to back up claims that this diet can be a helpful tool for weight loss, hormone and blood sugar balance, etc. but it needs to be done smart. Nutrient deficiencies can occur with this eating style if someone is neglecting to add vegetables and color to their plate. I like Dr. Anna Kebeca’s “keto-green” approach. Fat and protein also help you feel full and satiety much sooner than carbohydrates, so you may also end up eating less overall as a result.

Cons: If you have any sort of medical condition you should always check with your doctor before starting this diet. It can be contraindicated in patients with pancreatitis, liver failure, disorders of fat metabolism, etc. Most reported side effects include nausea, vomiting, headache, muscle fatigue, dizziness, irritability, and constipation. This is sometimes referred to as keto flu and symptoms resolve in a few days to 2 weeks as your body adjusts. Be sure to drink plenty of water and stay hydrated while following this diet!

PALEO: Also referred to as the “caveman diet” which is a dietary plan based on foods similar to what might have been eaten during the Paleolithic era before farming became the way of life. What you can eat: fresh fruits, vegetables, lean cuts of meat (beef, veal, lamb, and pork- no processed or cured meats allowed), chicken or turkey without skin, fatty fish, nuts and seeds, and oils from fruits and nuts (ex: olive oil and walnut oil)… all foods that in the past could be obtained by hunting and gathering. Grains, legumes, refined sugar, salt, potatoes, and dairy are a no no.

Pros: I think the hypothesis of the Paleo diet is bogus, but I do think this eating style will help you clean up your diet as it cuts out all processed foods. Weight loss will likely occur if you make the switch from a highly processed diet to a Paleo style of eating- duh! You’re cutting out all additives, preservatives, and chemicals which will also have anti-inflammatory benefits. With a higher intake of protein, healthy fats, and fiber you’re also likely to feel more full and satiated.

Cons: This diet may be challenging for very active people and athletes because of the grain and dairy limitations. Whole grains and dairy are easy quick energy food sources for athletes; therefore, getting adequate carbs from fruits and vegetables may be challenging for athletes. This diet is also so limited on the “allowed” foods that it may be challenging to get enough variety and/or eat socially. I believe there are ways to clean up your diet without having to go full blown paleo.

VEGAN/VEGETARIAN: This style of eating eliminates animal protein and/or all animal products. This style of eating has really regained popularity recently, especially after the Netflix documentary The Game Changers (which I wrote an entire post about it here in case you missed it).

Pros: I think a lot of health benefits that are observed when someone changes their diet to vegetarian or vegan eating style is because they are cutting out a lot of junk they might have been eating before. They are likely including more fresh fruits and vegetables and less fast food hamburgers. Poor quality and highly processed meat is not healthy, so cutting that out will make a significant positive impact on health. However, in my well researched opinion, high quality animal protein can be part of a very healthy diet. I talk a lot about that in this post.

Cons: I too often see people blindly cutting out meat and/or animal products in the name of animal cruelty or health without doing their research and having a solid game plan. One day they are eating eat and the next day they aren’t, but don’t have a clue what to replace the nutrients they were getting from animal products from anymore.

If you’re going to cut out an entire (and very important) food group you better have a solid plan on how you’re going to get in those nutrients elsewhere. I often work with vegetarians who consume a carbohydrate heavy diet and get their “protein” from highly processed meat alternatives. Unless carried out in a very thoughtful and educated way, a vegan or vegetarian diet can lead to nutrient deficiencies, weight gain, and other side effects. I’m not saying it’s impossible to meet your nutrient needs by follow an animal free lifestyle, I know many people that do, but it takes work. I will also throw in that I do not think a vegan diet is appropriate for young children.

GLUTEN FREE (GF): Is a diet that was developed for patient’s suffering from Celiac disease. Gluten is a protein found in many grains. The gluten found in wheat, barley, rye can trigger an autoimmune response in those who suffer from celiac disease. Celiac is a condition in which gluten triggers immune system activity that damages the lining of the small intestine. Over time this damage prevents the absorption of nutrients from food. Back in the days when I was learning about celiac and gluten free diets in college, there were very minimal gluten free food options for celiacs and those options were very expensive. Now gluten free products are EVERYWHERE and there are so many food product options these days for people with celiac and a gluten sensitivity. Gluten free diets gained popularity a while back when people thought that it would help aid in weight loss.

Pros: An obvious “pro” is that this diet is essential for people with true celiac disease or intolerances. If you’re having issues with inflammation, gut health, or other health conditions that might be a response to gluten, then it might be worth doing an elimination diet and see how you feel. You can also experiment and figure out what dose or specific foods you can tolerate or not tolerate. If going gluten free helps you cut out a lot of processed foods for more fresh fruits and vegetables- then yes that is an obvious perk to the diet. You can still follow a very balanced diet eating gluten free. There is also some evidence to support that cutting out gluten can improve lactose intolerance in celiac patients because of the gut repair that takes place when gluten is cut out.

Cons: The idea that gluten free products are “healthier” just because they have a gluten free label on them is very misleading and false. There seems to be a “halo of health” around gluten free products and that is completely false. A gluten free cookie is not inherently healthier than a whole wheat flour cookie. Packaged gluten free products can still be highly processed, loaded with sugar and vegetable oils, and are typically lower in fiber.

INTERMITTENT FASTING (IF): Intermittent fasting is a style of eating in which you go without food for a certain amount of time each day. There are several different IF styles like time restricted eating, 12 hour fasting, alternate day fasting, 5:2 fasting, once a month fasting, and I’m sure their are more.

I was initially very against this “trend” because of my background in treating eating disorder. While I stand firm that this eating style is not appropriate for someone with an active or recent history of an eating disorder/disordered eating behaviors I have recently thrown myself into the research and many reputable sources that support IF and it’s potential health benefits.

Pros: For many people this way of eating can help simplify eating because there is a smaller window of time to have to make food decisions. Possible health benefits: weight loss, improve blood sugar balances and reduce insulin levels, reduced inflammation, heart health, autophagy (is the body’s way of cleaning out damaged cells, in order to regenerate newer, healthier cells) and the list of potential benefits goes on.

Cons: Like I said, this is not an appropriate diet for anyone with an active or recent history of an eating disorder. This eating style can be a set up for binge eating episodes, obsessive thoughts about food, or other disordered eating behaviors. The research is mixed, but IMO prolonged fasting (>12 hours) is not ideal for a women trying to conceive.

Any diet plans you’re curious about that I missed? Leave them in the comments section of DM us!

xx, A

Disclaimer: All information on the The Champagne Theory blog, including but not limited to information about nutrition, health and fitness, is intended for general or background purposes only, and not as medical advice applicable to any individual. Please consult your medical provider or providers for instructions specific to your own medical concerns and condition.