Starting the New Year with a New Diet? Read This

It’s the New Year, and everybody’s ready for a “new you”—maybe you are too. You’ve probably heard the buzz about all the many trendy diets out there, but just because they’re trending doesn’t mean they’ll work for you. We asked Margaret Mangan, registered dietitian at REX Wellness Center of Raleigh, to break down these pros and cons of these diets based on what you’ll be eating, how much effort it takes to stick to the regimen, and how it could affect your body.


The Origin: The Whole30 diet started as an experiment carried out by two sports nutritionists in 2009. The blog of their month-long journey started trending like crazy, and by 2016, #Whole30 was dominating Instagram. Its creators say it will “put an end to unhealthy cravings and habits” and help people realize how different types of food affect them.

The Food: Eat unprocessed meats and seafood, fresh fruits and veggies, eggs, nuts and seeds. Avoid all processed foods, added sugar, legumes, dairy and alcohol.

The Effort: While this diet is only intended to be used for 30 days, it takes quite a bit of planning and willpower. It will require frequent grocery store trips and meal planning. Whole30 will also force you to learn a lot about food in general, because in order to avoid all the undesirables on this diet, you have to know what’s in everything you’re eating.

The Takeaway: Whole30 is essentially an elimination diet, similar to ones used by doctors to pinpoint a type of food that’s causing a patient discomfort. It’s hard to stick to, even for a month, and could lead to people frequently falling off the wagon, Mangan says. And if you slip, you’re supposed to start over with a fresh 30 days.

“Any time you start restricting things, it kind of makes me cringe,” Mangan says. “When you eliminate foods people want them more.”

Mangan also isn’t on board with eliminating legumes. She says beans are a great source of protein, especially for vegetarians and vegans.

On the other hand, if you have some bad food habits and decide to try this diet for the suggested 30 days, Mangan says it could be beneficial.


The Origin: Paleo is short for Paleolithic, because this diet dictates followers eat only what would have been available to hunter-gatherers in the prehistoric era. In the 1980s and ‘90s, several doctors put their heads together and thought, “Hey, if it worked for them, why not us?”

The Food: Eat unprocessed meats and seafood, fresh fruits and veggies, eggs, nuts and seeds. Processed foods are a no-no, along with grains, dairy and legumes, because our cavemen ancestors wouldn’t have had access to these foods.

The Effort: While the diet is very similar to Whole30, it’s not as restrictive. You can use sweeteners like honey or splurge every now and then on a glass of wine because it’s more of a “what works best for you” diet, while Whole30 is a strict regimen designed to eliminate certain foods from your body.

The Takeaway: Because Paleo expects you to sustain the elimination of multiple foods from your diet, Mangan is not a fan. She says the increased flexibility compared to Whole30 is good, but you’re still snubbing foods that deliver your body key vitamins, minerals and other nutrients, especially from dairy.

“Dairy is the hands-down best source of calcium. You can get it from other sources, but you won’t get as much as you get from milk because it’s processed by your body differently,” Mangan says.

And because of all the restrictions, this diet might get old fast for your taste buds, unless you’re especially creative in the kitchen.


The Origin: Modern-era veganism started in 1940s in England as a non-dairy form of vegetarianism. Since then, it has morphed into a fully-minded practice to respect animals and the environment by consuming only plant-based foods. Some vegans even go the distance by eliminating all animal-made or based products (clothes, toiletries, décor) from their lives.

The Food: Eat fruits and vegetables—lots of ‘em— along with whole grains, legumes, nuts and seeds. Any kind of animal product, whether it’s meat, milk, cheese or eggs, is not allowed.

The Effort: You definitely need to learn how to read an ingredients label to be vegan. Animal products pop up in places you wouldn’t have considered. For example, some orange juice brands boost amino acids by adding fish oil. The number of vegan options out there is growing, but this diet is a lifestyle change that requires dedication. Sticking to it is usually easier if you’re committed to the cause.

The Takeaway: Mangan says it’s absolutely possible to sustain this in a healthy way, but she does recommend some supplements. Because we were genetically developed with meat as a part of our diet, eliminating it could lead to a B12 deficiency. Mangan stresses how important B12 is for prenatal care and for proper development in growing children.

“If you don’t get enough vitamins like B12, it can stunt growth and development. Your body doesn’t work like it should,” Mangan says.

If there’s a possibility you could be pregnant or if you have a little one at home, you need to consult your doctor about what kind of diet would be best.


The Origin: Ketogenic, often shortened to keto, is a diet first prescribed by doctors in the 1920s to people suffering from epilepsy. Its low-carb, high-fat approach— coupled with just enough protein—changes the way energy is used in the body. It essentially turns your body into a fat-burning machine, hence the recent popularity amongst dieters.

The Food: Eat foods high in healthy fats and non-starchy vegetables; eat limited amounts of protein from meat, chicken and seafood. Some fruits, dairy, nuts and seeds are allowed. The big no-no’s here are grains, processed food and anything else high in carbs.

The Effort: You definitely have some more wiggle room here. Eating out is easier than on many diets. If you aren’t a skilled cook, you can still throw together some good, simple meals. However, you do need to educate yourself on which foods are allowed and why.

The Takeaway: Mangan is not a fan. She says unless a person is dealing with seizures or another medical issue, this is not a healthy diet. Keto severely cuts carbs and replaces them with fattier foods, which leads to poor cardiovascular health and bad cholesterol.

“The body needs somewhere between 45 to 65 percent of its intake coming from carbs,” she says.

Mangan says you can drop quick pounds with keto, but not in a healthy way.


The Origin: It’s right there in the name: flexible vegetarian. This diet is the brainchild of a vegetarian nutritionist who wanted to eat the occasional hamburger without feeling guilty. While many people have been consuming meat in this reduced fashion for centuries, the term flexitarian became popular in the 21st century.

The Food: Eat vegetables, fruits, grains and the occasional meat, chicken or seafood. The majority of this diet is vegetarian, but allows animal products a couple of times a week.

The Effort: As the least restrictive of all the diets on this list, it allows you to focus less on what you can and can’t eat, and more on living life. It allows more freedom in the kitchen and eating out, as long as you still make health-conscious decisions.

The Recommendation: Jackpot! Mangan says this is a commonsense, balanced approach focused on fruits and vegetables that doesn’t limit protein or dairy intake.

“You almost can’t even call this one a ‘diet’ because it’s so easy to stick to,” she says. “Flexitarianism is very sustainable as a long-term diet.”

Even though your meat consumption takes a backseat on this diet, when you do go for protein, Mangan says to go for the lean stuff.

The Expert’s Advice

There’s no one-size-fits-all diet. Each person has different needs, and you may not find success with the same diet your friend is following. The biggest question you need to ask yourself about a diet is, “Can I live with this?”

That question spans all areas of your life. Can you be healthy on this diet? Can you still live the life you want? Can you afford this diet? Life is difficult enough without having to follow a diet that makes you miserable, Mangan says. To lose weight or get healthier, you don’t have to hop on board the trending diet train.

“You just have to be mindful of what you’re putting in your body. Eat lots of fruits and vegetables, lean proteins, and monitor your salt and sugar intake,” she says.

And yes, you can indulge—in moderation—because, as Mangan says, “Who doesn’t like cake on their birthday?”

If you want something more structured, Mangan is a champion of the Mediterranean, MIND and DASH diets. They are all very similar and offer overall good health effects.

The Mediterranean diet is based on what people living around the Mediterranean Sea eat, and the MIND and DASH diets are adaptations of that diet. With all three, you eat fruit, vegetables, whole grains, nuts and legumes, along with fish and chicken. Red meat and dairy products are allowed, but should be eaten less often. Instead of salt, focus on herbs and spices to give food flavor, and use olive oil instead of butter.

Before starting a new diet, it’s always good to sit down with a doctor or a dietitian to talk about what’s best for you.

Want to schedule an appointment with a dietitian? Contact REX Wellness Centers or UNC Wellness Centers.