Fad diets might seem tempting: They promise to melt fat instantly, detoxify your body, boost your energy and even improve your heart health. But do they?
"Some fad diets eliminate a lot of healthy foods that could be beneficial to your heart," says Nicolette Jones, clinical dietitian at The University of Kansas Health System. "Generally, we don't want to eliminate the opportunity for good nutrition and whole natural foods in the diet."
Could your diet be harming your heart? Read on to find out.
5 popular diet trends
1. Gluten-free
Gluten is a type of protein found in barley, wheat and rye. While most people have no problem digesting gluten, some people – such as those with celiac disease – are unable to process gluten and experience digestive upsets when eating gluten-containing foods. However, gluten has gotten a bad rap and many healthy people choose to go gluten-free to lose weight or adopt healthier eating habits.
"There are 2 ways you can go with this diet," Jones says. "You can either buy a lot of processed gluten-free products or choose whole foods like brown rice, fruits and vegetables that are really heart healthy and full of fiber."
What you can have:
- Rice
- Corn
- Ancient grains
- Fruits and vegetables
- Meat and poultry
- Fish and seafood
- Dairy
- Beans, legumes and nuts
What you can't have: Any products containing wheat, barley or rye
- Bread
- Cereals
- Pastas
- Beer
- Pizza
- Baked goods
Heart health concern: Overindulging in processed gluten-free products, eliminating some whole grains
"Just because something says it's gluten-free doesn't mean it's not packed with added sugar and saturated fat," Jones says. "So you have to have to approach this diet in a way that eliminates gluten but still incorporates healthy fruits and vegetables."
Bottom line: Gluten isn't poison. Unless you have celiac disease or gluten intolerance, you probably don't need to go gluten-free. In fact, incorporating whole grains like wheat, barley and rye into your diet can actually boost your heart health.
2. Vegan/vegetarian
Many people eliminate meat, dairy and other animal products by adopting a plant-based vegetarian or vegan diet. This could be due to personal beliefs – whether for animal rights or the environment. But it can be for health reasons, too, as animal products are often linked to health issues. Nutritionally, vegan and vegetarian diets are high in whole fruits, vegetables, legumes and grains.
"Both diets could be beneficial for heart health," says Jones. "It's just about following the diet correctly."
What you can have:
- Fruits and vegetables
- Whole grains
- Dairy (vegetarian only)
- Legumes, nuts and seeds
- Soy
What you can't have:
- Meat and poultry
- Fish and seafood
- Dairy (vegan only)
- Honey (vegan only)
Heart health concern: Free rein on carbohydrates, fat and sugar
With the restriction of meat or animal products, it can be tempting to load up on refined carbohydrates, fat and sugar since they aren't off-limits.
"You could eat bread and cheese all day and call yourself a vegetarian," Jones says. "So again, it's about making good choices and incorporating lots of fruits and vegetables, plant-based protein and less processed dairy."
Bottom line: A vegan or vegetarian diet can be beneficial for your heart health when done the right way. Jones recommends avoiding over-processed dairy, cheese and soy products and choosing whole, natural foods.
3. Paleo
Eating like a caveman is the guiding principle of the Paleo diet. The idea is to get back to basics with a more natural diet that consists of only what a person could hunt or forage in prehistoric times. Proponents of Paleo eating argue that this type of diet is better suited to our bodies' natural digestive processes than a modern, agricultural-era diet. They also claim going Paleo can help you lose weight fast and lower your risk for developing chronic health conditions.
"I don't think it's necessarily a diet that would be really heart unhealthy," Jones says. "But there's a right and wrong way to do it."
What you can have: Anything a caveman could eat
- Grass-fed meats
- Fish/seafood
- Fruits and vegetables
- Eggs
- Nuts
- Seeds
- Healthy oils (flaxseed, olive, avocado, walnut, coconut)
What you can't have:
- Grains
- Legumes (including peanuts)
- Dairy
- Processed meats (hot dogs)
- Refined sugar/soft drinks/fruit juices
- Potatoes
- Processed foods
- Overly salty foods (ketchup)
- Refined vegetable oils
- Starchy vegetables (in moderation)
- Alcohol
Heart health concern: Eliminates several food groups, can be high in saturated fat
"It's mainly a diet of meat and low-carb vegetables," Jones says. "It encourages more whole foods, which is great, but it does run the risk of being high in saturated fat – which we're finding more and more isn't the most detrimental type of fat. But we can see how overconsuming saturated fats affects your cholesterol levels."
Completely eliminating certain food groups, like whole grains, is also problematic. Especially since whole grains have been shown to reduce your risk of cardiovascular disease.
"Whole grains are going to have fiber, B-vitamins and other nutrients we need daily. So, when you eliminate that source of nutrition, you have to get creative," Jones says. "I don't like to tell heart patients to eliminate a whole food group because it becomes unrealistic. We want to encourage making small, long-term changes to your diet in a heart-healthy way."
Bottom line: Adopting some of the basic principles of Paleo eating that emphasize a more whole-foods-based approach can be advantageous for heart health. But something like the Paleo diet, which can be highly restrictive, eliminates sources of heart-healthy nutrition as well.
4. Low-fat
If you have heart disease, you're probably very familiar with following a low-fat diet, which restricts fatty meats and includes low-fat pastas, breads and grains. But recently, studies have shown that diets high in refined carbohydrates can actually be worse for your heart than a high-fat diet. However, doctors still discourage eating too many fatty foods.
What you can have: Most low-fat foods
- Oatmeal and cereal
- Pastas
- Crackers
- Bagels, breads and English muffins
- Fruits and vegetables
- Lean meat, poultry and fish
- Reduced fat or nonfat dressing
- Low-fat cheese and dairy
What you can't have:
- Fatty meats
- Oil
- Butter
- Avocado
- Full-fat dressings
- Mayonnaise
- Cookies, pastries and other baked goods
- Full-fat cheese and dairy
Heart health concern: High in refined carbohydrates and processed foods
"A low-fat diet is usually really carb heavy. Most people will have an extra intake of sugars and starchier carbohydrates," Jones says. "And research is finding that sugar has been a pretty big culprit for heart disease all along because of how it links to cholesterol and blood sugars, and the inflammatory impact of that."
Bottom line: Fat isn't always the enemy. In fact, replacing healthy fats with starchy, processed carbohydrates and sugars can actually be more detrimental to your heart health. Aim for a good balance of heart-healthy fats in your diet (think fish, healthy oils and avocado) and replace refined carbohydrates with whole grains.
5. The Whole 30
The Whole 30 is a diet that emphasizes eliminating "craving-inducing, blood sugar disrupting, gut-damaging, inflammatory food groups" for a full 30 days. This includes sugar, dairy, grains and legumes.
"It's a kind of challenge for people who are doing well with their diet, but who want to take it one step further," Jones says. "It helps you see how your body reacts to sugar and refined foods by eliminating them completely, and then reintroducing some of these items back into your diet to see if there's a sensitivity."
What you can have:
- Meat and poultry
- Fish and seafood
- Eggs
- Some fruit
- Vegetables
- Natural fats (avocado, healthy oils)
- Ghee or clarified butter
- Fruit juice
- Green beans, sugar snap peas and snow peas
What you can't have:
- Any added sugar (real or artificial)
- Alcohol
- Grains
- Legumes
- Dairy
- Carrageenan, MSG or sulfites
- Baked goods, junk food or sweets
Heart health concerns: Not sustainable, restrictive
"The Whole 30 can show how some of these processed, higher sugar foods affect us," Jones says. "But it's not something we would recommend for a lifetime."
Bottom line: The Whole 30 is a great challenge diet that can better help you understand your food sensitivities. However, Jones says it is too restrictive for heart patients in the long run.
"This is the kind of diet we wouldn't want a heart patient to have for more than 30 days," Jones says. "When you eliminate beans and other plant-based products, you miss out on an opportunity to get protein and heart-healthy fiber from those items."