Are you eating enough?
Too much or too little? The amount should be just right..
How do we lose fat?
A calorie deficit is required for fat loss. Where do we start with knowing what a calorie deficit is? There are basic math equations that have been used in the health industry for decades to provide an estimate of a person’s metabolic rate based on things like their height and weight… and then you factor in activity level to come up with a number that should be pretty close to a person’s “maintenance calories”. This of course is just an estimate, because there is a little bit of variability between people, and things like health issues should also be factored in. So then from that amount, you subtract calories to create what we call a calorie deficit. When you eat fewer calories than your body needs, you are putting it in a position where it is required to then draw from your fat stores in order to provide the energy your body needs to function.
The question then becomes, how much of a deficit should you put yourself in? There are a few factors to consider. A “typical” deficit would consist of around 500 cal less than where you maintain your current weigh. But that’s only going to give you about a pound of loss per week on average, which if you have a lot of weight to lose would be painfully slow. Or, maybe you have an event coming up where you want to lose a larger amount in a short amount of time. For these circumstances and others, a larger deficit might be more appropriate so that faster loss can be achieved. The cons of this would be that of course you’re eating less food, so you’re going to be more hungry, have less energy, and perhaps have a higher chance of “falling off the wagon. But, if you like seeing fast lost to keep you motivated, and feel psychologically able to deal with the hunger, then it might be a good option for you. (Note that if protein is kept high enough, and resistance training is utilized, loss of lean mass should be mitigated even in a larger deficit.)
What is NOT true is that not eating enough is going to cause you to not be able to lose fat or to gain fat (“starvation mode”).
There are lots of factors to consider when deciding if you were going to diet aggressively or more reasonably… both approaches have pros and cons and neither should be immediately discounted.
Starvation mode, in a sense it was presented, does not exist. Cutting calories and losing weight will reduce your calorie expenditure. Still, the starvation mode will not cause you to gain weight.
Starvation mode is the long term effect of calorie restriction and weight loss. However, it is not what you hear on the mainstream media.
Your body won’t go into starvation mode because you skipped breakfast, or you forgot to snack in the middle of the day.
Make your eating schedule fit your lifestyle and personal preferences. Stay in a calorie deficit at the end of the week if your goal is to lose weight. Your metabolism is not a delicate flower, and it can handle a few hours of not eating. However, avoid following extremely low-calorie diets and don’t attempt to lose more than 1% of your body weight per week.
How do you know if you are causing metabolic slow down by activating the so-called starvation mode?
Signs and symptoms of starvation mode
1. You are always hungry: During a weight loss diet, it is reasonable to feel hungry from time to time. This is just temporary and a small sacrifice for a bigger reward. However, if your hunger becomes a problem and causes you to binge, this is a sign of something going wrong.
Hunger is controlled by hormones, leptin, and ghrelin. Leptin makes you feel full, whereas ghrelin makes you feel hungry. As we lose weight, leptin levels go down, and we feel hungry. Since leptin is released from the fat cells, it is natural to have less leptin as you lose fat. However, it has been shown that leptin levels drop as a response to a large calorie deficit regardless of fat loss.
2. You feel lethargic: If you feel too tired to do the things you usually do, you may be experiencing the effects of starvation mode. Getting out of bed, going to the gym, cleaning your house, or taking the stairs seems too much and you just want to take a nap instead, the calories you burn through NEAT is decreasing. As a result, you won’t burn as many calories throughout the day, and your weight loss will slow down or stop altogether.
3. You hit a weight loss plateau: If you eat the same amount of calories and exercise the same way. Still, you no longer lose weight, you may be experiencing starvation mode. There are two things to consider before jumping to conclusions. First of all, as you lose weight, your calorie needs will be lower. Therefore you need to re-calculate your calorie need after losing weight. The second point is that weight loss is never linear. Bodyweight fluctuates, and not losing weight in a few days is not alarming.
If you fail to lose weight two weeks in a row, then it’s time to make a change. But if your calories are low enough and you exercise the same way, then you are probably not burning as many calories through NEAT due to starvation mode.
4. You feel cold: Studies have shown that long term calorie restriction may lower the body’s core temperature. If you feel unusually cold all the time, even in warm temperatures, you may be in starvation mode. This is an extreme consequence, and you may be pushing too far with your weight loss. Lower body temperature is also a sign of lower BMR. Therefore you will burn fewer calories even during rest.
How to Get Out of Starvation Mode
If you think you are in starvation mode, here are some ways to get out of the starvation mode:
1. Eat Adequate Calories: If your goal is to lose weight, you must eat fewer calories than you burn. However, creating too big of a calorie deficit may cause you to get into the starvation mode. After calculating your total daily energy expenditure (TDEE), create a calorie deficit of 20-30%.
The appropriate rate of fat loss is 0.5-1% of your total weight. Losing weight faster than this will cause lean body mass loss and slow down your metabolism. Slow and steady weight loss is the way to go for long-term, sustainable results.
2. Eat More Protein: Out of three macronutrients, protein requires the most amount of energy to digest. Increasing the protein content in your diet will not only increase the calories burned through TEF, but it will also increase lean body mass. Increased lean body mass is associated with higher BMR.
3. Lift Weights: In a study, Hunter et al. showed that “Exercise training prevents a decrease in energy expenditure, including free-living energy expenditure separate from exercise training, following weight loss. Lifting weights will also help you preserve or increase lean body mass during weight loss. As I mentioned before, more lean mass means more calories burned every day.
4. Take Diet Breaks: Byrne et al., in the famous MATADOR study, found that 2 weeks on, 2 weeks off diet works better than staying in a consistent calorie deficit. Taking diet breaks will attenuate the effects of low-calorie consumption on leptin levels. For a diet break to work, it needs to be somewhere between 2 days and 2 weeks. Diet break doesn’t mean you can eat whatever you want. During the diet break, you need to increase your calorie intake to the maintenance level and not anymore. You can take a break from your diet for a few days every time you experience a weight loss plateau.
References:
1. Donahoo, W. T., Levine, J. A., & Melanson, E. L. (2004). Variability in energy expenditure and its components. Current Opinion in Clinical Nutrition & Metabolic Care, 7(6), 599-605.
2. Fothergill, E., Guo, J., Howard, L., Kerns, J. C., Knuth, N. D., Brychta, R., … & Hall, K. D. (2016). Persistent metabolic adaptation 6 years after “The Biggest Loser” competition. Obesity, 24(8), 1612-1619.
3. Rosenbaum, M., & Leibel, R. L. (2010). Adaptive thermogenesis in humans. International journal of obesity, 34(S1), S47.
4. Chin-Chance, C., Polonsky, K. S., & Schoeller, D. A. (2000). Twenty-four-hour leptin levels respond to cumulative short-term energy imbalance and predict subsequent intake. The Journal of Clinical Endocrinology & Metabolism, 85(8), 2685-2691.
5. Soare, A., Cangemi, R., Omodei, D., Holloszy, J. O., & Fontana, L. (2011). Long-term calorie restriction, but not endurance exercise, lowers core body temperature in humans. Aging (Albany NY), 3(4), 374.
6. Hunter, G. R., Fisher, G., Neumeier, W. H., Carter, S. J., & Plaisance, E. P. (2015). Exercise training and energy expenditure following weight loss. Medicine and science in sports and exercise, 47(9), 1950.
7. Byrne, N. M., Sainsbury, A., King, N. A., Hills, A. P., & Wood, R. E. (2018). Intermittent energy restriction improves weight loss efficiency in obese men: the MATADOR study. International journal of obesity, 42(2), 129.