From the keto diet to intermittent fasting, to the carnivore diet or counting macros, you or someone you know probably found a certain level of success losing weight while following one of these diets. 

Just as each diet is unique, so is each person. From the type of food someone can afford to the amount of exercise they fit into each day, there are many human factors that can affect the success of a diet plan. 

Trendy diets can work, but it is essential to do your research so you can make informed decisions about which diet will work best for your body, lifestyle and goals. We’ve rounded up a few trending diets to give you a head start. Read on and get ready to start building healthy habits and achieving your goals.

Keto Diet

Erin Mahoney is vice president of education at International Sports Sciences Association (ISSA).

The ketogenic diet is defined as, “a nutritional approach consisting of high fat and adequate protein content but insufficient levels of carbohydrates for metabolic needs, thus forcing the body primarily to use fat as a fuel source.” It’s a fairly straightforward definition, but why or how does it work?

With very low carbohydrate intake, the body shifts the primary energy source from blood sugar (glucose derived from carbs) to ketones, which are derived from fat by the process of ketogenesis. Ketones act as a fuel source when glucose is in short supply. They are produced when very few carbs and a moderate amount of protein make up a diet.

On this weight loss plan, dieters are encouraged to eat lots of grass-fed butter, olive oil, cheese (think cheddar, feta, and bleu), heavy cream, and MCT (medium-chain triglycerides) oil.

The keto diet may be a good option for people who are overweight, obese or prediabetic, however it is recommended dieters get the approval of their physician before starting. The diet may not be the best option for athletes or those looking to build muscle, as it could contribute to loss of strength. 

Intermittent Fasting

Intermittent fasting is a style of eating rather than a restrictive diet, which is a major appeal for a lot of people looking to trim down. Fasting does not have anything to do with what you eat, rather when you eat. 

It is a simple pattern of eating that shifts between designated periods of fasting—not eating at all or severely restricting calorie intake—and periods of eating healthfully. Exactly when and for how long the fasting periods last depends on individual choice. 

Research indicates that this style of eating does help with weight loss and can provide a number of health benefits, while risks are low. A benefit of intermittent fasting is that it promotes fat loss, not just weight loss. Fasting triggers human growth hormone, which is beneficial for fat loss and muscle gain. Fasting also increases insulin sensitivity, another hormone change that results in loss of fat.

Intermittent fasting shows great promise for a variety of people, both for weight loss and for overall good health. Just remember that it’s not for everyone, and that the most important thing to remember is to eat a healthy, well-balanced diet that avoids junk and empty calories, whether you choose to fast or not.

Counting Macros

Those who rave about this diet are most often drawn to counting macros for weight loss because all foods—including jumbo chocolate chip cookies, loaded baked potatoes, and fried chicken—are allowed, as long as they “fit your macros.” This is in stark contrast to most other diets which restrict the types of foods you’re allowed to consume.

Generally speaking, an individual should consume more carbohydrates to achieve lean mass gains and fewer carbs to achieve fat loss. The ideal macro profile for each person is dependent upon their goals. Here’s a cheat sheet to get you started: 

• To build muscle: 30-40% carbs, 25-35% protein, 15-25% fats

• For fat loss: 10-30% carbs, 40-50% protein, 30-40% fats

• To maintain: 30-50% carbs, 25-35% protein, 25-35% fats

Counting macros can be a great plan for those looking to lose fat or build muscle, however, if you find counting calories to be tedious, you won’t be excited to hear that you need to weigh and measure your foods in order to track macros. 

The Right Diet for You

Each of these trending diets are great options, depending on your goals and lifestyle. When choosing the right diet for you, it’s important to remember that all of these plans force the user to follow the first rule of good nutrition: controlling your energy balance. 

It is not a magical, mythical macronutrient mix; the energy flowing out of the body must exceed the energy flowing into the body to achieve weight loss. Building healthy habits that support goals for a healthy lifestyle is the most important aspect of any diet plan.


Erin Mahoney is vice president of education at International Sports Sciences Association (ISSA). ISSA is a global leader and pioneer in the fitness and nutrition personal training certification industry. For more than 30 years, ISSA has been committed to providing the highest quality certification program by merging the gym experience with practical applied sciences in order to help people achieve their goals. Curently, ISSA has trained more than 200,000 students and placed personal trainers across 92 countries, all while continuing to develop greater access to opportunities that promote a healthier world. For more about ISSA, visit