Myth Buster: All Calories are Created Equal
When talking about weight loss and maintaining a healthy weight, have you ever heard a nutrition expert say something like, "calories in versus calories out is all that matters…”? But then there's no explanation as far as how to choose your calories wisely? Traditional training in nutrition leads many to believe that all calories are created equal when it comes to weight, and that it doesn't really matter where your calories come from as long as you have the proper balance of in versus out.
Then why do so many people still struggle with their weight when they follow the recommended calorie targets? Why do so many individuals feel the need to follow other diets like low carb, low fat, weight watchers, etc.?
Well... because it's not really that simple. The mantra of, "calories in versus calories out," can ring true in a healthy individual with no underlying metabolic or hormonal conditions who has good lean muscle mass and eats a perfectly balanced diet. But that's not most people in America...
When I google, "how many calories do I need," the first website that comes up is a calculator from the Mayo Clinic. I plug in my information and choose an "active" activity level and I get 2150 calories.
I personally don't count calories now, but I used to when I was in my early 20s and if I ate 2150 calories a day then, I would consistently gain weight. So curiously, I decided to plug in my information from when I was 22 and was WAY more active (before having tiny children) so I chose the “very active” activity level. It calculated my needs for when I was 22yrs old would have been 2600 calories a day. NO WAY could I eat that many calories then. I was counting and would eat no more than 1500-1800 and still barely keep the weight off (and was hungry all the time!).
But now, I'm in my 30s, never count calories, eat the most food I've ever eaten in my life, eat cookies and ice cream here and there, eat homemade baked goods I make with my toddler almost weekly, and don't gain weight. If I estimate how many calories I probably eat in a day, I likely surpass 2150 many days in my week.
Let's dig into some factors that play into how food choices impact our ability to use calories efficiently.
1. Caloric Quality vs. Quantity
Definition of Calories
Calories are units of energy our bodies use to perform various functions, from breathing to running. Not all foods that provide calories offer the same benefits or impacts on our overall health.
Nutrient Density
When we talk about nutrient density, we mean how packed a food is with nutrients like vitamins, minerals, antioxidants, etc. relative to how many calories it has. For instance:
Leafy Greens (e.g., spinach, arugula, kale): These are high in vitamins A, C, K, folate, and fiber while being low in calories.
Berries (e.g., blueberries, raspberries, strawberries): These also are low in calories but are loaded with antioxidants that help combat oxidative stress and inflammation, reducing the risk of chronic diseases.
Nuts and Seeds (e.g., almonds, walnuts, chia seeds): These have a decent number of calories but provide many healthy fats, protein, and essential minerals like magnesium.
In contrast, foods that are high in sugar and refined carbohydrates supply many "empty calories". Meaning they provide calories/energy but little to no benefit when considering other nutrients. These foods might make you feel full temporarily but can lead to poor overall health and hormone balance.
Impact on Health
Eating nutrient-dense foods supports overall health by ensuring your body gets the essential nutrients it needs to function optimally. On the other hand, relying on empty-calorie foods can lead to a range of health issues. The lack of fiber, healthy fats, essential vitamins and minerals, etc. can lead to deficiencies that promote problems like weakened bones, poor immune function, hormone issues, anemia, etc. Additionally, high refined carbohydrate and sugar filled diets are linked to increased risk of conditions like obesity, type 2 diabetes, heart disease, infertility, etc.
2. Metabolism and Hormone Balance
Decreased Metabolism/Basal Metabolic Rate (BMR):
First, let's define basil metabolic rate (BMR). Our BMR is the minimum number of calories we need to survive basic functions in the body like breathing, digesting, etc. You can think about it like this: if you were to sit on the couch all day, how many calories would you burn? That's your BMR. Two examples of how food impacts BMR include:
BMR and Muscle Loss: Diets deficient in essential nutrients, especially protein, can lead to muscle loss. Since muscle is metabolically active (meaning it burns a lot of calories even while resting), this decreases our basal metabolic rate.
Thyroid Function Impairment: Insufficient intake of nutrients like iodine and selenium can hinder thyroid hormone production. These hormones are crucial for regulating metabolism, and disruptions can lead to a decreased BMR.
Hormonal Imbalance:
Another way types of food impact out weight include how our dietary choices impact our hormones. Hormones are the chemical messengers in our body and they tell the body what to do and when to do it. How does this impact our weight? I'll give 3 examples:
Cortisol (A Stress Hormone): Poor dietary choices, such as excessive caffeine and sugar, can raise cortisol levels, which in turn can increase appetite and fat deposition. High cortisol can decrease BMR and increase fat around the abdomen even if calorie intake does not increase.
Ghrelin and Leptin (Appetite Hormones): An imbalanced diet can disrupt the normal function of ghrelin (the hunger hormone) and leptin (the satiety/full hormone), leading to increased hunger, overeating, and weight gain.
Thyroid Hormones: As mentioned, inadequate nutrition can impair thyroid function, resulting in altered levels of thyroid hormones, further decreasing metabolism and energy levels.
These interconnected effects highlight how crucial a balanced diet is for maintaining optimal metabolic health and balanced hormone levels, all of which are key to overall well-being and effective weight management.
3. Changes in the Gut Microbiome Impacting Metabolism:
Diversity of Gut Microbiota:
Low Fiber Intake: A diet low in fiber affects the diversity of the gut microbiome (bacteria in our gut that are involved one way or another in nearly every body system). Fiber-rich foods like fruits, vegetables, legumes, and whole grains feed beneficial bacteria, promoting diversity that is crucial for good health. Without sufficient fiber, less beneficial bacteria may dominate, which can lead to health issues including obesity.
High Sugar and Fat Intake: Diets high in processed sugars and unhealthy fats can promote the growth of harmful bacteria and reduce the overall diversity of the gut flora. This imbalance, known as dysbiosis, can negatively impact metabolism and increase fat storage.
Reduced Microbial Diversity: High-fat, high-sugar diets can diminish the diversity of the gut microbiome, leading to the dominance of bacteria that are more efficient at extracting calories from food, potentially increasing weight gain.
Production of Short-Chain Fatty Acids (SCFAs):
Fermentation by Gut Bacteria: Beneficial gut bacteria ferment fibers and produce something called short-chain fatty acids. These SCFAs help regulate fat metabolism and insulin sensitivity, protecting against obesity. Some research shows that one of these called Acetate can even pass into the brain to decrease appetite.
Short-Chain Fatty Acids (SCFAs) Reduction: A low-fiber diet starves beneficial bacteria that produce SCFAs, which are important for healthy metabolic function. Lower levels of SCFAs can impair fat and sugar metabolism, contributing to weight gain and insulin resistance.
The health of the gut microbiome is deeply interconnected with dietary habits and body weight.
Practical Implications and Conclusion
So how does one improve their diet to support metabolism, hormone balance, and gut health? By focusing on a whole food, minimally processed, low added sugar diet. For a thorough overview of what this means, check out my blog titled, "Embrace a Healthy Diet: Essential Guide to Balanced and Nutritious Eating." But for a brief overview:
Fruits and Vegetables: Include a wide variety of fresh or frozen fruits and vegetables. Emphasize a colorful assortment to ensure a broad intake of different nutrients and antioxidants.
Whole Grains: Incorporate grains that have all three parts intact (the bran, germ, and endosperm), such as whole wheat, brown rice, oats, barley, and quinoa. Avoids refined grains like white rice and white flour, which lack the fiber and nutrients found in whole grains.
Proteins: Focus on high quality meats and avoid fried, breaded meats. Reduce intake of processed meats like imitation meat, sausage, poor quality deli meat, and hot dogs.
Nuts and Seeds: Encourage a variety of nuts and seeds, which provide healthy fats, proteins, and other beneficial nutrients. Focus on raw or dry-roasted nuts without added salts or flavorings.
Dairy and Dairy Alternatives: Choose unflavored/unsweetened milk, yogurt, and cheese. Plant-based alternatives should be minimally sweetened and unflavored. Check labels to avoid added sugars and excessive processing.
Healthy Fats: Use oils that are extracted naturally, such as olive, avocado, and coconut oil. Avoid against hydrogenated oils and trans fats, which are often found in processed foods. Minimize the use of seed and vegetable oils such as soybean, corn, sunflower, canola, safflower, grapeseed, and cottonseed.
Herbs and Spices: Use herbs and spices for flavoring instead of vegetable-oil / sugar-filled sauces and dressings. Use both fresh or dried varieties without added fillers.
This diet minimizes or eliminates:
Highly processed snacks and sweets, such poor-quality crackers, chips, cookies, and candy.
Fast foods and heavily processed ready-to-eat meals.
Artificial sweeteners, preservatives, additives and colorings.
Understanding that not all calories impact your body the same way can help you make better food choices. By focusing on nutrient-dense foods, being aware of how different nutrients affect your metabolism and satiety, you can support your overall health more effectively. Remember, it’s not just about how many calories you eat but also the quality and source of those calories when it comes to maintaining a healthy weight and promoting overall health.
