Prevalence of Obesity in the US


Obesity has become an alarming epidemic in the US. According to the Center of Disease Control (CDC), 36.5% of adults and 17% of children and adolescents in the US are obese – that’s nearly 1 out of every 3 adults and 1 out of every 8 children – and these statistics are from 2014 and are continually rising1. To be classified as obese as an adult, a person’s body mass index (BMI) must be greater than 30 kg/m2. As an adolescent, defined as children aged 2-19, a child’s BMI must be at or above the 95th percentile for their respective sex and age group.

What is Body Mass Index?

Body mass index is an individual’s weight in kilograms divided by the square of an individual’s height in meters2. BMI is a simple and easy screening tool for weight categories determined by the CDC. Weight categories include underweight, normal weight, overweight and obese. These categories for children and adults are described below:

Curious as to where you fall? Use the CDC’s Adult BMI calculator.

Why are obesity rates so high?

Ask a group of people what they think about Americans and I’m sure at least a few of them will say “fat and lazy” and technically, they aren’t completely incorrect. A study from the World Health Organization found a positive relationship between the increase in average annual fast food transactions per capita and the increase in average BMI in high income countries, including the US3. This makes sense considering fast food makes up around 11% of the average American adult’s diet4.

When it comes to inactivity, it’s practically the new norm. Most Americans spend their days sitting at a desk, this includes children attending school. If you think about it, there are much more corporate jobs available now then their were 50+ years ago, when most Americans were working in fields or factories – jobs that require much more physical activity than your average desk job today. According to the CDC, 23.7% of American adults engage in no leisure-time physical activity and only 20% of American adults meet aerobic and muscle strengthening guidelines set out by the CDC5. The guidelines include at least 150 minutes a week of moderate-intensity aerobic physical activity or 75 minutes a week of vigorous-intensity aerobic physical activity and muscle-strengthening activities on 2 or more days a week6.

If you are curious as to how you stack up with the current CDC guidelines on physical activity, you can head over to their fact sheet.

How does obesity affect your life?

There are many consequences and comorbidities that are associated with obesity. Some of the common consequences are listed below2:

  • Mortality
  • High blood pressure
  • Type 2 Diabetes
  • Coronary heart disease
  • Sleep apnea and breathing problems
  • Low quality of life
  • High burden of care
  • Difficulty with physical function

What can we do about it?

Sometimes we may not realize that obesity is preventable. Obesity does not happen all at once, but one pound at a time. There are plenty of healthy lifestyle changes that you can adopt to prevent obesity.

  • Be active! Simple changes can help. Take the stairs instead of the elevator, walk around your office when you take phone calls, walk your dog, aim to get your 10,000 steps a day in, join a gym or group fitness classes… The possibilities are endless!
  • Eat a healthy diet. Does this mean eating salads for every meal? Of course not. But limiting portion sizes or limiting the amount of times you eat fast food in a week can give you a good starting point.
  • Sleep! Yeah, you heard that right. Getting adequate amounts of sleep can help you keep your BMI where it should be. It is recommended that adults over the age of 18 get 7 or more hours of sleep7.
  • Build your army. Get your family involved, your friends involved, or even hire a health coach. There is strength in numbers and people out there willing to help you achieve your goals.

Not sure where to start? I recommend using the USDA’s Body Weight Planner to help you set goals for balancing food and activity.



  1. Ogden CL, Carroll MD, Fryar CD, Flegal KM. Prevalence of obesity among adults and youth: United States, 2011–2014. NCHS data brief, no 219. Hyattsville, MD: National Center for Health Statistics. 2015.
  2. “Body Mass Index (BMI).” Centers for Disease Control and Prevention. Centers for Disease Control and Prevention. 2015.
  3. De Vogli R, Kouvonen A, Gimeno D. The influence of market deregulation on fast food consumption and body mass index: a cross-national time series analysis. Bulletin of the World Health Organization. 2014: 92(2): 77-152.
  4. Fryar CD, Ervin RB. Caloric intake from fast food among adults: United States, 2007-2010. NCHS data brief, no 114. Hyattsville, MD: National Center for Health Statistics. 2013.
  5. “Physical Activity: Data and Statistics.” Centers for Disease Control and Prevention. Centers for Disease Control and Prevention. 2015.
  6. U.S. Department of Health and Human Services.2008 Physical Activity Guidelines for Americans. Hyattsville, MD: U.S.Department of Health and Human Services, 2008.
  7. Watson NF, Badr MS, Belenky G, et al. Recommended amount of sleep for a healthy adult: a joint consensus statement of the American Academy of Sleep Medicine and Sleep Research Society. Sleep. 2015;38(6):843–844.

What is IIFYM?

“If it fits your macros,” aka IIFYM, is a diet plan where each individual has their own personal goals for how much macronutrients they should consume over the course of a day. It is a form of “flexible dieting,” which allows people to have cheat meals or certain foods they like as long as they fit into their daily macronutrient count.

So let’s back up for a minute… What are macronutrients? The main macronutrients, or macros for short, include carbohydrates, fats, and protein. They are required in a normal diet and are consumed in large amounts. They are the nutrients that our bodies break down for energy. These are different from your micronutrients, which include vitamins and minerals, and are consumed in much smaller amounts.

How do you figure out what macros are right for you? First, you’re going to have to calculate your Total Daily Energy Expenditure, or TDEE. Your TDEE is the amount of calories your body requires to maintain its current state, based on how active you are during the day along with your height, weight, gender, and age. Out of pure convenience, head on over to to easily calculate your TDEE.

  • Example: I am a 22 year old female, 5’7″ and 145 lbs. I am a student so I am moderately active. My TDEE is 2250 calories per day.

After calculating your TDEE, you must establish your goals to determine how many calories you should eat each day. Are you trying to gain muscle mass? Burn fat? Maintain? Your goals will greatly affect the amount of macros recommended for your diet. To put it simply:

  • Gain weight: add and extra 20% of your TDEE (example: 2250+(2250 x 0.20) = 2700 calories)
  • Lose weight: subtract a maximum of 20% of your TDEE (example: 2250-(2250 x 0.20) = 1800 calories)
  • Maintain: use your TDEE (example: 2250 calories)

Now, we can calculate your macros!

  • Protein is normally set around .825g per pound of body weight. If you’re like me and weightlifting is a part of your exercise regimen, you can set yours at 1 gram per pound of body weight (example: 145lbs = 145g protein per day). One gram of protein = 4 calories… So 580 calories of my TDEE are attributed to protein.
  • Fat is set at 25% of your TDEE. So if I want to lose weight, my fat intake would be 1800 x .25 = 450 calories of fat. Because 1 gram of fat = 9 calories, I should eat 50 grams of fat per day.
  • Carbohydrates are calculated as the rest of your available TDEE (1800-580-450= 770 calories). Because 1 gram of carbs = 4 calories, I should eat about 190 grams of carbs per day.

So in conclusion, a diet for a 145-lb, 5’7″, 22 year-old female wanting to burn fat is as follows:

  • 1800 calories per day
  • 50 grams fat per day
  • 145 grams protein per day
  • 190 grams of carbs per day

Not too bad, right? IIFYM provides simple guidelines to delegating your calories wisely so you can consume all of the macronutrients your body needs. I love IIFYM because if I am missing out on fats or carbs by the end of the day, sometimes I can squeeze in a pop tart or some toast and peanut butter. Being able to diet flexibly makes me feel less guilty about eating one of my grandma’s cookies during a family party or sharing a milkshake with my little brother as long as it is within my macros.

There are plenty of arguments against flexible dieting, and I can understand why. Some claim IIFYM allows you to eat higher quantities of salt, unhealthy fats, and refined carbohydrates. Some also claim clean eating is better, because the ingredient lists are shorter and you are eating less processed food. 

Like I say with just about anything, I think balance is key. Almost 90% of my IIFYM-calorie diet consists of clean and unprocessed foods. I personally try to avoid processed foods as much as possible, but still like to eat my Oikos vanilla Greek yogurt in the mornings. I’m also gluten and oat free, which can make things a little complicated. I think IIFYM is a great tool as long as you are not filling your macros entirely with processed foods, refined carbs, and unhealthy fats. 

  1. Ioannides, Z. A., Ngo, S. T., Henderson, R. D., McCombe, P. A., & Steyn, F. J. (2016). Altered Metabolic Homeostasis in Amyotrophic Lateral Sclerosis: Mechanisms of Energy Imbalance and Contribution to Disease Progression. Neurodegenerative Diseases, 16(5-6), 382-397.
  2. Miller III, E.R., Erlinger, T.P., & Appel, L.J. (2006). The effects of macronutrients on blood pressure and lipids: An overview of the DASH and omniheart trials. Current Atherosclerosis Reports, 8(6), 460-465.
  3. Robert-McComb, J.J., Álvarez Carnero, E., & Iglesias-Gutiérrez, E. (2013). Estimating Energy Requirements. The Active Female. 411-449.