{"id":579,"date":"2026-01-16T10:11:56","date_gmt":"2026-01-16T15:11:56","guid":{"rendered":"https:\/\/site.extension.uga.edu\/diabetes\/?p=579"},"modified":"2026-02-27T10:26:40","modified_gmt":"2026-02-27T15:26:40","slug":"calories-in-calories-out-whats-it-all-about","status":"publish","type":"post","link":"https:\/\/site.extension.uga.edu\/diabetes\/2026\/01\/calories-in-calories-out-whats-it-all-about\/","title":{"rendered":"Calories in, calories out: what&#8217;s it all about?"},"content":{"rendered":"\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-28f84493 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<p><\/p>\n\n\n\n<p>&#8220;Calories in, calories out&#8221; &#8211; or CICO &#8211; has been the traditional rallying cry to explain weight management. When the number of calories consumed matches the number of calories burned, weight remains the same. Too many calories in or not enough out? Weight gain. Not enough calories in or too many out? Weight loss. It sounds simple. Let&#8217;s break down what goes into this seemingly simple mathematical equation to explain energy balance.<\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"683\" src=\"https:\/\/site.extension.uga.edu\/diabetes\/files\/2026\/01\/balancing-stones-1024x683.jpg\" alt=\"\" class=\"wp-image-778\" srcset=\"https:\/\/site.extension.uga.edu\/diabetes\/files\/2026\/01\/balancing-stones-1024x683.jpg 1024w, https:\/\/site.extension.uga.edu\/diabetes\/files\/2026\/01\/balancing-stones-300x200.jpg 300w, https:\/\/site.extension.uga.edu\/diabetes\/files\/2026\/01\/balancing-stones-768x512.jpg 768w, https:\/\/site.extension.uga.edu\/diabetes\/files\/2026\/01\/balancing-stones-1536x1024.jpg 1536w, https:\/\/site.extension.uga.edu\/diabetes\/files\/2026\/01\/balancing-stones-750x500.jpg 750w, https:\/\/site.extension.uga.edu\/diabetes\/files\/2026\/01\/balancing-stones.jpg 1800w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n<\/div>\n<\/div>\n\n\n\n<h2 class=\"wp-block-heading\">Calories in<\/h2>\n\n\n\n<p>We&#8217;ll start with the good stuff; calories in. Calories are a unit of energy. Our bodies need a source of energy 24\/7 and we get calories from the macronutrients in food, including protein, carbohydrate, and fat. Food provides us with that direct energy source &#8211; calories &#8211; as well as essential nutrients to support our bodily functions, like water and fat soluble vitamins and minerals. For a simple two letter phrase &#8211; calories in &#8211; there are a number of complex factors that influence the calories our bodies take in. These include:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Energy needs: our energy needs are <a href=\"https:\/\/cdn.realfood.gov\/DGA.pdf\" data-type=\"link\" data-id=\"https:\/\/cdn.realfood.gov\/DGA.pdf\">influenced by factors<\/a> that include age, sex, height, weight, activity level, and health conditions. <\/li>\n\n\n\n<li>Types of food eaten: anyone who has tracked their food intake can tell you that the amount and type of foods we eat can vary greatly in their energy density and nutrient content. Energy dense foods are those which have a relatively high number of calories while being low in nutrients; conversely, nutrient dense foods provide essential nutrients while being low in saturated fat, sodium, and added sugars. Some macronutrients are more calorie-dense than others; carbohydrates and protein contribute 4 calories per gram while fats provide 9 calories per gram. Alcohol provides 7 calories per gram. Alcohol is a toxin which <a href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/11115785\/\" data-type=\"link\" data-id=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/11115785\/\">cannot be stored in the body and is prioritized in metabolism<\/a>, meaning the body will metabolize and clear the body of alcohol before beginning to utilize other macronutrients.<\/li>\n\n\n\n<li>Digestion and absorption: not all bodies are the same. Digestion and absorption of food &#8211; as well as the types of food eaten &#8211; vary from person to person. Some bodies are more efficient and absorb more energy from food than others. Health conditions like inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), cystic fibrosis, and other malabsorptive conditions can greatly impact digestion and absorption of nutrients.<\/li>\n\n\n\n<li>Physical hunger: hunger is the physical need to eat which is a result of signals from the body, like low blood glucose or the hormone ghrelin that signals to the brain that we need to eat. We might notice physical hunger in a variety of ways; a rumbling tummy isn&#8217;t the only cue that we&#8217;re hungry. Difficulty concentrating, racing or cloudy thoughts, feeling anxious or distracted, and even a bad mood &#8211; yep, that&#8217;s &#8220;hanger&#8221; coming to let us know it&#8217;s past time to eat. Our energy needs impact our physical hunger.<\/li>\n\n\n\n<li>Appetite: while hunger is a biological need for food, appetite is our mental drive to eat. It&#8217;s influenced by physical hunger, but also happens in response to environmental cues. Our appetite can kick into gear when we&#8217;re in a particular place or with certain people, when we see or smell food, or when we&#8217;re experiencing emotions like sadness, happiness, or even boredom. <\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Calories out<\/h2>\n\n\n\n<p>We covered the calories in and now it&#8217;s time to talk about how we burn that energy. There are various ways to <a href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/11115785\/\" data-type=\"link\" data-id=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/11115785\/\">estimate energy expenditure<\/a>, with most gold-standard scientific methods being inaccessible for the average person. The most common way to estimate energy expenditure is through <a href=\"https:\/\/www.calculator.net\/bmr-calculator.html\" data-type=\"link\" data-id=\"https:\/\/www.calculator.net\/bmr-calculator.html\">predictive energy equations<\/a>. The Mifflin St. Jeor equation is considered to be among the most <a href=\"https:\/\/www.andeal.org\/template.cfm?template=guide_summary&amp;key=621\" data-type=\"link\" data-id=\"https:\/\/www.andeal.org\/template.cfm?template=guide_summary&amp;key=621\">reliable and accurate<\/a> predictive energy equation for healthy adults.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Resting metabolic rate: the <strong>resting metabolic rate (RMR)<\/strong> is the amount of energy used by the body while at rest. This can be measured in a laboratory setting or estimated using predictive energy equations such as the Mifflin St. Jeor mentioned above. Our resting metabolic rate is in turn influenced by a number of factors; genetics, body size and composition, age, health conditions, and medications, to name a few. RMR accounts for roughly <a href=\"https:\/\/www.nationalacademies.org\/read\/26818\/chapter\/6\" data-type=\"link\" data-id=\"https:\/\/www.nationalacademies.org\/read\/26818\/chapter\/6\">60-70% of daily energy expenditure<\/a>.<\/li>\n\n\n\n<li>Thermic effect of food (TEF): this is the energy required to digest, absorb, and metabolize the food that you eat, which results in an increased metabolic rate after a meal. Just like macronutrients had differences in caloric density, some require more energy to metabolize. Protein has the highest TEF, followed by carbohydrates and fats. TEF typically comprises about 10% of daily energy expenditure. Meal composition, size, and frequency are all known to affect TEF.<\/li>\n\n\n\n<li>Energy burned through exercise: this is known as <strong>exercise activity thermogenesis (EAT)<\/strong>. It includes intentional exercise, like swimming, cycling, or walking. The energy we burn through exercise depends on a number of factors; first, the types of activities we enjoy and engage in. Our physical abilities come into play here, too. The intensity, duration, and frequency of exercise has a major impact on the energy we burn. It can also be influenced by our environment; factors like temperature, air quality, altitude, and climate all impact the amount of energy used during exercise. <\/li>\n\n\n\n<li>Energy burned through non-exercise activity: this is known as <strong>non-exercise activity thermogenesis (NEAT)<\/strong>. NEAT includes energy utilized for non-intentional exercise. This could include light housework, child care duties, job related movement, or leisure activities. It even includes fidgeting or other repetitive movements that we don&#8217;t even realize we&#8217;re doing. Typically, NEAT is light intensity activity. The combination of EAT and NEAT account for about <a href=\"https:\/\/www.ncbi.nlm.nih.gov\/books\/NBK20371\/\" data-type=\"link\" data-id=\"https:\/\/www.ncbi.nlm.nih.gov\/books\/NBK20371\/\">30% of daily energy expenditure<\/a>. However, it&#8217;s widely variable depending on the activity level of the individual, with highly active people burning more energy through physical activity. <\/li>\n<\/ul>\n\n\n\n<p>In summary, yes, energy balance is a matter of calories in matching calories out. But reducing energy balance to this very simple equation can do a disservice to individuals because it doesn&#8217;t address the many variables contributing to each side of the energy balance equation. It&#8217;s challenging to accurately count the calories we consume and energy expenditure is not a static number that remains the same from day to day. For these reasons, it&#8217;s important to keep in mind the complexity of human energy balance.<\/p>\n\n\n\n<p><\/p>\n","protected":false},"excerpt":{"rendered":"<p>&#8220;Calories in, calories out&#8221; &#8211; or CICO &#8211; has been the traditional rallying cry to explain weight management. When the number of calories consumed matches the number of calories burned, weight remains the same. Too many calories in or not enough out? Weight gain. Not enough calories in or too many out? Weight loss. It [&hellip;]<\/p>\n","protected":false},"author":539,"featured_media":778,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9,8],"tags":[],"class_list":["post-579","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-cdpsm","category-nutritionandhealth"],"_links":{"self":[{"href":"https:\/\/site.extension.uga.edu\/diabetes\/wp-json\/wp\/v2\/posts\/579","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/site.extension.uga.edu\/diabetes\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/site.extension.uga.edu\/diabetes\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/site.extension.uga.edu\/diabetes\/wp-json\/wp\/v2\/users\/539"}],"replies":[{"embeddable":true,"href":"https:\/\/site.extension.uga.edu\/diabetes\/wp-json\/wp\/v2\/comments?post=579"}],"version-history":[{"count":2,"href":"https:\/\/site.extension.uga.edu\/diabetes\/wp-json\/wp\/v2\/posts\/579\/revisions"}],"predecessor-version":[{"id":779,"href":"https:\/\/site.extension.uga.edu\/diabetes\/wp-json\/wp\/v2\/posts\/579\/revisions\/779"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/site.extension.uga.edu\/diabetes\/wp-json\/wp\/v2\/media\/778"}],"wp:attachment":[{"href":"https:\/\/site.extension.uga.edu\/diabetes\/wp-json\/wp\/v2\/media?parent=579"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/site.extension.uga.edu\/diabetes\/wp-json\/wp\/v2\/categories?post=579"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/site.extension.uga.edu\/diabetes\/wp-json\/wp\/v2\/tags?post=579"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}