I wish there was a hard and fast definition for weight loss and fat loss – I think we too often use them interchangeably and, in some cases, I find myself doing the same because it can be hard for some to understand there’s a difference. Looking around for language, it’s clear than many experts from both fitness and the medical community use these terms interchangeably for ease.
Fat loss is just that –body fat has been burned and can reflect on the scale (gravity), but also in your measurements (the space we take up). This doesn’t fluctuate greatly on a day-to-day basis.
Weight loss, however, can vary greatly and is compromised of water loss, fat loss and muscle loss. Hydration and mineral balance are highly variable and can impact the scale on a day-to-day basis. Mineral balance and other hormonal fluctuations are highly variable and can change on a day-to-day basis.
This post, is going to talk about fatloss and weight loss unchangeably because I’m unsure a better way to explain it.
When we think of losing weight, losingfat, we think we must be burning more calories than we’re consuming. That’s partially true.
There are at least three factors that go into losing, maintaining and gaining weight and mass.
- Calories you’re consuming
- Calories you’re burning
- Hormonal balance (sleep, stress, menstrual cycle fluctuations/menopause, suboptimal organ function like hypo or hyperthyroidism)
On average, it takes 3,500 calories in excess to lose a pound of fat,reversely, on average it would take about 3,500 in excess to gain (Thompson, Janice; Manore, Melinda, 2015, p. 396). There’s moreresearch out there about this, but this post isn’t about that – maybe another time. There are allowable discrepancies on nutrition labels such as calorie rounding and caloric deduction of fiber and sugar alcohols from the overallcalories reported on a label, but it’s still relatively easy to track nutritional intake.
There are many tools that can assist in tracking this like My Fitness Pal (which is what I used for a number of years and recommend), MyMacros, etc. At the end of the day, you need to be honest with yourself regarding the number of calories you’re consuming, which means you need to be honest about your portions. It’s easy to over eat dense foods from nuts to sweets, in a bubble – tracking for weight loss needs to be specific and leaves minimal room for error, while your diet as a whole should provide flexibility for diversity (and accounts for social/emotional behavior).
As far as hormonal balance, inrelation to the menstrual cycle, many who track their ovulation may be able totell when fluctuations are happening. Symptoms like breast swelling, bloating, fatigue, back pain and cramps are a few signs of hormonal shifts during different phases of the menstrual cycle (U.S. Department of Health and Human Services, 2018).
Without blood work, it can be difficult to determine which specific hormones are shifting. Outside from menstrual cycle, for most, it can be hard to pinpoint what causes are contributing to hormonal disruptions. Internal causes for hormonal disruptions outside of the menstrual cycle can be related to external causes such as an increase in cortisol caused by stress at work, which is impacting sleeping patterns, eating behaviors, exercise (Fricchione, Ivkovic, & Yeung, 2016). Other internalcauses may be from suboptimal organ function such as hypo- (underactive, not producing enough thyroid hormones) or hyper- (overactive, producing too muchthyroxine hormone) thyroidism impacting the body’s ability to metabolize nutrients (Mayo Foundation for Medical Education and Research, 2018). There are other illness/diseases/disorders that cause metabolic disruptions and hormonal imbalances (PCOS, etc).
So, what about the calories you’re burning – well, they are and aren’t in your control.
Here’s some vocabulary, I’m sure you’ve seen some of it floating around.
Basal metabolic rate or BMR is the energy required for optimal function (Thompson, Janice; Manore, Melinda, 2015, p. 397). This is what yourbody needs to function including breathing, circulating blood, building muscle and developing new cells, brain function and nutrient processing and transport.
It’s common to see BMR and resting metabolic rate (RMR) used interchangeably. RMR is the calories burned per unitof time at rest. It’s usually measured after being fasted for about eight orhours. It may be more accurate than BMR, but only slightly.
BMR and RMR take into consider age, height,weight and gender – so it’s understood that BMR and RMR will decrease as aperson lose weight and ages. After the age of 30, a decrease of “approximately 3-5% per decade” will occur as a result of hormonal changes and changes in lean body mass (Thompson, Janice; Manore, Melinda, 2015, p. 397).These are influenced by lean body mass, “which is more metabolically active than fat mass” – meaningit uses a lot of energy to carry out function and will result in burning more calories, so individuals have the ability to increase their BMR and RMR as they increase their lean body mass (American Council on Exercise, 2013, p. 213). BMR accounts forbetween 60 to 75% of your daily energy expenditure.
The thermic effect of food is the energy required to digest, absorb andstore ingested food. This accounts for about 5-10% of daily energy expenditure, meaning if a meal is around 500 calories, it will take between 25-50 calories to process that meal. Each nutrient (fat, carbohydrates and protein) do take different amounts of energy to break down and utilize with carbohydrates and protein needing the most energy and fats needing the least (Thompson, Janice; Manore, Melinda, 2015, pp. 397-398).
The thermic effect of physical activity is broken into two categories: non-exercise activity thermogenesis (NEAT) and exercise (American Council on Exercise, 2013, p. 211).Essentially, daily movement that isn’t planned like going to work, walking to the mailbox (if you get mail), going to the grocery store as well as planned activity like going to the gym. The combination of activity can account for 15to 30% of daily energy expenditure and is highly variable because it relies on individuals.
While we can control how we workout toincrease our lean muscle mass, we ultimately don’t have much control over our BMR. We also don’t have control over energy needs for metabolizing food especially if there is organ system impairment (a physician will be able to assist a patient determine if and how to correct this). Our NEAT is within our control and is oftensomething we forget about.
Our NEAT is the reason that we see progress speed up or slow down when we change jobs or any large component of our routine. If you’re used to sitting for large portions of the day, it’s reasonable to see weight loss when you start standing or walking for large portions of your day instead. The reverse, if you’re used to working in a restaurant where you’re on your feet for long hours, you would see your body potentially maintaining or gaining weight once you become sedentary.
Both components of thermic effect ofphysical activity are highly variable and for much of the population, it’s reasonable that exercise actually doesn’t make much of an impact and NEAT is a larger factor in if the individual will lose, maintain or gain (Levine, 2007).
A full week is 168 hours, so if a person exercises five days a week for 30 minutes, they are utilizing 150 minutes or 2.5 hours of their week for exercising. However, this is barely 1.5%of their time in a 7-day period (week). Using myself as an example: getting upat 7 or 7:30 am and staying up until 11 or 11:30 pm five days a week (as my “workweek”) accounts for about 40% of my week. If I’m sitting the whole time thiswill be more impactful than the 1.5% in the gym.
Together the three components make up our total daily energy expenditure or TDEE. Once understanding and concluding an estimation of total calorie burn, an individual can determine more effectively how to change their caloric intake to work towards losing, maintaining or gaining in a healthful way.
It’s highly likely that your TDEE will vary day-to-day as your routine changes, however, striving to maintain your NEAT from day-to-day will assist in your goals and help keep your TDEE relatively consistent (Levine, 2007). For example, itwould be reasonable to maintain an after-work walk on the weekends so that youhave some consistency in your NEAT throughout the whole week not just the work week.
Any changes to your NEAT or your exercise should be determined and looked through a long-term lens, meaning youneed to ask yourself “Is this maintainable for life?” or “Will it be easy to transition from losing to maintaining or maintaining to losing or gaining, etc?”.
A review by J.A. Levine discussed necessity for personal approaches to increasing NEAT to assist in weight loss that also recognized environmental limitations such as inability to change a sitting deskto a standing desk to promote-NEAT activity (Levine, 2007).
Using positive reinforcement strategies, he discussed the approach STRIPE:
S – select a NEAT-activity that is enjoyed and start it
T – targeted, specific individual goals must be defined
R – rewards need to be identified for reaching the defined goals
I – identify barriers and remove them
P – plan NEAT-activity sessions (like going for a walk or getting up out of your chair for a few minutes every hour)
E – evaluate adherence and efficacy
This approach should be utilized for a healthy lifestyle as a whole to help improve adherence (Alkerwi, et al., 2015). Many things influence our activity levels and our ability to adhere to our goals, taking into consideration limitations caused by environmental, socioeconomic, health-related and behavior factors is going to be key to success overall.
References
Alkerwi, A., Schuh, B., Sauvageot, N., Zannad, F., Arnaud, O., Guillaume, M., . . . Larssaon, C. A. (2015). Adherence to Physical Activity Recommendations and Its Associated Factors: An Interregional Population-Based Study. Journal of Public Health Research, 406.
American Council on Exercise. (2013). The Physiology of Obesity. In A. C. Exercise, ACE Health Coach Manual (pp. 201-224). Washington DC: American Council on Exercise.
Fricchione, G. L., Ivkovic, A., & Yeung, A. S. (2016). The Science of Stress: Living Under Pressure. Chicago: The University of Chicago Press.
Levine, J. (2007). Nonexercise Activity thermogenesis – liberating the life force. Journal of Internal Medicine, 273-287.
Mayo Foundation for Medical Education and Research. (2018, November 25). Diseases and Conditions. Retrieved from Mayo Clinic: https://www.mayoclinic.org/diseases-conditions
Thompson, Janice; Manore, Melinda. (2015). Achieving and Maintaining a Healthful Body Weight. In J. Thompson, & M. Manore, Nutrition: An Applied Approach (pp. 389-439). San Francisco: Pearson.
U.S. Department of Health and Human Services. (2018, November 26). Menstrual Cycle. Retrieved from Office on Women’s Health: https://www.womenshealth.gov/menstrual-cycle/your-menstrual-cycle 0
