If you’re like most, sometimes figuring out what a healthy diet actually consists of might seem as confusing as trying tofigure out how to put together a piece of Ikea furniture.
For the most part, basic nutrition is pretty straightforward, but the fact that we’re constantly bombarded with different diet theories and varying research results quickly and constantly clouds what we think we know and often makes us second guess our choices. When it comes down to it, though, the answer to many of our most common diet questions is an unsatisfying one: it depends. This is because—and maybe you’ve heard this before—what works for one person might not be the best option for another.
Of course, like we just said, this answer is entirely unsatisfying and mostly just leaves us wondering how exactly we can go about finding what does work best for us. Part of figuring out what your best diet will consist of includes educating yourself. This is where the experts come in. We recruited six nutrition experts to answer some of the most commonly asked questions about diets and eating healthy.
Here’s what they had to say.
“Almost every nutrition expert will agree on certain points,” explained Dr. Caroline Cederquist M.D., creator of bistroMDand author of The MD Factor Diet. “The best diet is one that is low in processed food, added sugars and is high invegetables, fiber and has enough lean protein to prevent muscle breakdown and loss. From there, there is huge discussion and divergence of ideas with diets high ingrains verses low-carb diets, diets low in fat verses diets with fat as the majority of calories. Some recommend animal protein as the preferred protein and on the other spectrum are those who feel a vegan diet is best.” At the end of the day, though, Cederquist emphasized the fact that the “best” diet will be the one that you find easiest to follow.
“When I am working with a patient it comes down to, ‘does your diet work for you?’” she explained. “A diet that works for you will have you at or close to your ideal weight, and you will have energy and strength. It is also important to note that your ideal diet will change with regards to your life situation. If you are very active you will be able to have more extras and treats in your diet than if you are sedentary. Sometimes our lives become sedentary for a time and our ideal diet needs to reflect that”
She continued, “If you have gained weight, the priority is to lose weight while maintaining your muscle by ensuring you have lean protein spread throughout the day. Calories also matter for weight loss and your carbs will need to be from vegetables, legumes and fruit primarily with less grains and, of course, less sweets.
“Despite recent talk about the ‘fat controversy,’ we still need to pay attention to fat. Saturated fat from meats still should be limited while healthy fats from avocados, nuts and olive oil should be enjoyed but we should still watch the portions.
"Again, it all comes down to finding a diet that works for you. If you’re on a diet you don’t like, you won’t stick with it. You need to find something that fits within your lifestyle. You can eat healthy food without feeling like you’re on a restricted diet.”
Carbs are generally looked down upon, but they’re not as detrimental as you may think. Many still want to know, though, can a low-carb diet actually help you lose weight?
“The short answer is yes—but as with most things, a simple yes or no won’t suffice,” said Katie Goldberg, M.C.N., R.D.N., L.D.N., a Chicago-based registered dietitian specializing in weight management, diabetes, postpartum nutrition and wellness.
“Many studies have tried to address the question of whether a low-carb or a low-fat diet is better for weight loss. In 2003, a randomized control trial published by the New England Journal of Medicine gave the edge to the low-carb in the short-term (six months). In 2014, a meta-analysis (i.e. compiling data from many studies) published in the Journal of the American Medical Association also gave a slight edge to low-carb diets in the short-term, but over the long-term the differences became negligible.”
So, once again, as Goldberg explained, “the answer is truly about which of the diets patients adhere to over the long-term.” In other words, it’s about determining which is more manageable for you.
Goldberg went on to explain the pros and cons of low-carb diets.
The good of low-carb diets: “For the typical American, cutting out carbohydrates really boils down to cutting out a lot of low nutrient foods like sugar-sweetened beverages and desserts,” she explained. “There is always a benefit to cutting these foods out of your diet—or at least limiting them. Low-carbohydrate diets focus on protein and fat, which provide satiety. In short, you feel satisfied. When it comes to hunger, almost no one feels deprived on a low-carb diet.
The bad of low-carb diets: “Carbohydrates are often cut out unilaterally, without taking stock of what nutrients are involved. For many people, low-carb diets end up meaning high-meat diets.” Goldberg said. “When I see patients cutting out entire food groups, I start to get nervous. Whole grains, legumes, fruits, vegetables and dairy all provide key nutrients that meat cannot provide. Also, food cravings often take over and make the low-carb diet unsustainable in the long-term."
Goldberg continued, “One very significant thing to keep in mind is that your body requires carbohydrates to function. Specifically, carbs are your brain’s preferred source of fuel. Sometimes a low-carb diet can leave you feeling fuzzy-headed. Carbohydrates are also the first source of fuel that your muscles use when you are active. You could be sabotaging your weight loss efforts if your low-carb diet keeps you feeling a little sluggish, makes you cut out of the gym early, or if your form suffers while you work out. Athletes should be especially cautious in cutting out carbohydrates without talking to a dietitian.”
Ultimately, Goldberg explained, you can't go wrong when you’re choosing high-quality, real foods that are minimally processed. “The exact ratio of each of those foods is customizable. A registered dietitian can help you find that balance to optimize weight loss without sacrificing enjoyment of food.”
“Yes! A protein- and fiber-rich breakfast gives your body the fuel it needs to keep you at your best all day long,” said Alexandra Miller, R.D., L.D.N., corporate dietitian at Medifast, Inc. “During the night, our metabolism slows down due to the low energy demand. Upon waking, a well-balanced meal breaks the night-long fast, revs up the metabolism, and supplies it with needed energy for the day. Furthermore, adults who eat breakfast are less likely to overeat in the evening. When your body feels starved for a long period of time, it often tries to compensate—this usually presents itself in the evening, causing people to overeat.
In other words, Miller explained, if you want to maintain a healthy metabolism and decrease or maintain your weight, it’s not a good idea to skip breakfast.
“Another reason to eat breakfast is because it is the perfect opportunity to take in healthy nutrients,” Miller added. “People who eat breakfast often have a healthier diet overall. They’re more likely to acquire the vitamins, minerals and fiber that are recommended for the day. By eating a variety of whole grains (oatmeal, unsweetened cereal, quinoa, whole grain bread, etc.), fruit (berries, apples, oranges, bananas, etc.), protein (egg whites, cheese, etc.), vegetables (spinach, peppers, mushrooms, tomatoes, etc.), and low-fat dairy (unsweetened almond milk or low-fat cow’s milk, non-fat Greek yogurt), and healthy fats (nuts such as walnuts or almonds, flax seeds, chia seeds, avocado) you’ll get a healthy dose of nutrients.”
“Eating too many calories, despite their source, will lead to weight gain,” Miller explained. “Eating fewer calories than the body burns throughout the day will lead to weight loss. The goal for weight maintenance is for the calories ‘in’ to equal the calories ‘out.' With that being said, the source of calories can significantly impact your blood sugar levels, energy, heart health, digestive system, immune system, appetite, mood—the list is extensive." For this reason, she said, not all calories can be considered equal.
“Calories from protein help promote satiety, which is why it is recommended to have about 25 grams of protein per meal,” Miller explained. “Look for lean sources so that you get the protein without excess calories. Calories supplied by whole grains, fruits and vegetables offer a slew of health benefits, the first of which is improved digestion and blood sugar regulation from dietary fiber intake. Dietary fiber also helps keep us full and satisfied, which may lead to a reduced intake of calories throughout the day if consumed in adequate amounts—aim for 25 to 35 grams per day.”
When it comes to comparing calories keep the following in mind: “Vitamins and minerals are supplied extensively through fruits and vegetables. They help support a healthy body. Whether it’s the immune, cardiovascular, musculoskeletal, endocrine, neurological, or integumentary (i.e. skin), vitamins and minerals keep your body at its best,” Miller said. “Fruits and vegetables are also naturally low in sodium, fat and calories, making them an even better option for acquiring nutrition.
“Calories supplied by processed meats, fried foods, high-fat meats, sugary drinks, high-fat and high-sugar sweets, and other non-nutritive foods cause calories to add up fast with little to no nutritional benefit. In addition to being void of vitamins, minerals and fiber, many of these foods, if consumed regularly, can lead to cardiovascular complications, diabetes, and weight gain or obesity. It’s easy to gain weight and throw blood sugar levels out of whack when these types of foods are consumed in large portions on a regular basis. So look for calories that supply your body with healthful nutrients. You’ll have more energy, better health and a smaller waistline.”
“It’s very difficult to generalize answers for these types of questions because the answer depends on so many factors,” said Natalie Rizzo, M.S., R.D., a New York City-based registered dietitian. “For instance, meal timing definitely matters for athletes or people who are very active because they need to properly fuel before workouts and refuel after workouts. This question also makes me think of the common myth that you shouldn’t eat before bed. Generally, it’s not great to go to a bed on a full stomach because lying down interferes with digestion and can cause heart burn. But eating right before bed will not cause weight gain. The only thing that can cause weight gain is eating more calories than you burn, and it doesn’t matter what time you eat them. So the bottom line is that it matters when you eat in certain circumstances, like for athletes or those that suffer from digestive issues, but most people are free to eat whenever.”
“I like the idea of eating smaller meals throughout the day because it prevents you from going too long without food and becoming ravenous,” Rizzo said. “It’s never a good idea to get to a point where you are so hungry that you will eat anything that is put in front of you. Eating four to five meals per day will keep you relatively full but never too hungry. That’s the goal. But if you can accomplish that feeling with three meals a day, then that’s fine too.”
“If you want to be specific, a person's fluid needs will be about one milliliter for every calorie they burn, so for the average person burning 2,000 calories a day, that's where the old standby of eight cups or two liters fits in,” explained Georgie Fear, a pro nutrition coach and author of Lean Habits For Lifelong Weight Loss. “If you exercise a lot, you may need 10 cups or 2.5 liters. The good news is that all fluid counts, even if it's caffeinated or flavored. You even get fluids from the fruits and vegetables you eat. I recommend estimating how many ounces of beverages you have in a day and if it's less than 64 ounces or eight cups, add some more by carrying a water bottle with you, adding a glass of water to meals as a habit, or drinking a bottle during your workout. If you are thirsty for more, don't fear drinking to your thirst. You'll know you are well hydrated when your urine is very light colored or nearly colorless.”
“As a daily, practice, I'd advise against it,” Fear said. “As a short-term (up to three days) experience to increase your awareness, it can be helpful to see where your calories are coming from. However, as an ongoing strategy it has many drawbacks. Long-term weight management can be attained more successfully by tuning into your body's hunger and satiety cues as the signals to eat and finish eating. Not only does this method save time and help you maintain a healthier relationship with your body, it is more accurate than counting calories or estimating your expenditure, taking into account day to day variations in the amount of energy you need.” See also: Why Calories Matter Less than You Probably Think
Especially if you don’t already get enough (which is true for most Americans), explained Sarah Waybright, a registered dietitian and the founder of Why Food Works, then yes, fiber can certainly help support your weight loss goals.
“Fiber is a non-digestible carbohydrate,” she said. “That means your body literally can't break it down and use it as calories, but it can bulk up meals to make you feel full. Fiber does act as food for the healthy bacteria that line your entire intestinal tract, though, and the type of bacteria your body contains may play a big role in weight gain.” Waybright continued, “The recommended amount of fiber is at least (at least!) 25 grams per day for a small woman, and most Americans only eat 16 grams per day on average. There are many fiber supplements on the market, but nothing beats the natural sources— fruits, vegetables, legumes, nuts, seeds and whole grains (no animal products contain dietary fiber), which also come loaded with vitamins, minerals and phytonutrients.” Waybright noted that because fiber can’t be digested, it moves through your gut, acting like a broom to move things along while absorbing water to stay soft.
“Some people experience digestive discomfort and bloating when they first start to eat higher amounts of fiber, but don't worry—just make sure to increase your water intake and your body will adjust,” Waybright said. “So add in fiber-rich foods to eat more, and weigh less: try nuts as a snack, a piece of fruit at breakfast, and beans or lentils at least a few times a week to start.”
As of recently, the term gluten-free has become synonymous with eating healthy. However, this is likely an exaggeration. As of right now, those who suffer from celiac disease (a genetic autoimmune disease that damages the small intestine) are the only people who definitely need to avoid gluten for health reasons. For everyone else, there’s probably no reason to avoid it and there’s no evidence to show that doing so can help you lose weight. "For the most part gluten has become the new 'it' thing to blame our weight loss struggles on," said Chris Cooper, a Precision Nutrition coach and a NSCA certified fitness professional. "Suddenly everyone has a gluten sensitivity. This gluten-free trend has caught on in part because we want to blame something for why we've gained weight or why we can't lose weight. It's easier to just demonize a certain food group than to actually take a hard look at our nutrition and make a real change." For a more in-depth look at eating gluten-free see: Should You Eat Gluten-Free?