With deprivation diets enjoying unabated popularity these days, it’s not uncommon to see individuals facing symptoms of malnutrition and metabolic damage. Granted, most people won’t ever get there, but in dedicated dieters and high performance individuals chronic undereating is a common theme.
But what does “too little” mean in the context of fat-loss and long-term physique success? What are symptoms of severe energy deficiency? And how do you lose fat without crashing your metabolism?
Here’s what you need to know.
Weight-loss and Your Metabolism
Do you want to lose weight? You have two options:
- Eat more and train more, or
- eat less and train less
Unless you’re very overweight to begin with, you cannot eat less and train more. Certainly not long-term. The problem? 99% of weight-loss programs have you doing just that, creating the perfect storm for metabolic shutdown and physique frustration.
Yes, you need to expend more energy than you consume over weeks and months to see results. And technically speaking, eating less and training more will get you there, but you gotta be smarter about it. You can’t kill yourself in the gym day in day out, while living off of chicken breast salads and the occasional rice cake. I mean you certainly can, but it won’t be pretty and your results will be anything but impressive.
If you habitually stray too far from your body’s energy balance, where calorie intake matches calorie output, you will suffer the consequences and you will fail.
Are You Eating Enough?
Dieting is a dangerous game if you don’t know how to play. These are the six most common symptoms of chronic malnutrition.
1. Bad mood
Energy = mood.
If you’re always irritable or feeling low on your diet, you’re either expending too much energy, or you’re not eating enough food (or both). While this might sound desirable for fat-loss, it comes at a cost.
Dieters frequently suffer from mood swings, anxiety and depression.
Why do you think eating burgers and cake feels so good? These high-calorie foods trigger a powerful dopamine rush in the brain. That’s your body telling you you did good (and you’ll live to see another day). Now, that doesn’t mean you should stuff yourself with junk every day. What it means is you need to occasionally raise your calories and/or introduce high calorie re-feeds to sustain metabolic integrity. Even during fat-loss dieting, you should (occasionally) have your cake and eat it.
2. Appetite is all over the place
The first 2 weeks of your latest “diet experiment” appetite and hunger seem very manageable. You’re motivated, energized and don’t really crave sweets and pasta. You’re all about the lean meats and veggies now. Fast forward to week 3 and you’re tossing and turning in bed dreaming of pizza and pancakes…
What the hell happened?
Ironically, athletes frequently report a loss of appetite during heavy training and calorie restriction. But periods of low appetite and low energy intake are always followed by periods of insatiable hunger and overeating.
To prevent these ups and downs you need a feeding routine that provides you with sufficient nourishment at regular intervals. Consume 3-4 meals spread throughout the day with proper workout nutrition to fuel your workouts (even on low calorie days).
Going too low in calories will come back to haunt you. Always.
3. Bad sleep
Trouble falling and/or staying asleep and needing excessive amounts (8h+) of sleep every night is another symptom of chronic energy deficiency (and the concomitant cortisol spike).
The high stress levels seen with overly restrictive dieting (and/or excessive physical activity) negatively impact your endocrine function, compromising sleep and recovery. You’re now actively promoting hormonal imbalances and physical degeneration (road to skinny fat).
4. Trouble in the bedroom (“Fahne auf Halbmast”)
As mentioned above, a calorie deficient diet raises stress levels in the body. Apart from messing with your sleep, high stress levels impede sex hormone production. To conserve energy and maximize your survivability, your body shuts down the reproductive function. Not my idea of a good time.
If you have the sex drive of an 85-year-old or trouble “performing”, stop and reassess your approach to weight-loss. This doesn’t just apply to males. Female athletes and physique competitors often battle with eating disorders, menstrual irregularities (or dysfunction), and low bone mineral density (known as the female athlete triad) due to chronic energy imbalance.
No, you don’t need hormone replacement and you can ditch the latest “scientifically proven” (lol) testosterone boosters sold online. What you need is ENERGY. Bump up your calories and lower your exercise intensity and/or duration. Maintaining energy balance, at least intermittently, is critical to restoring hormonal balance.
5. Decreased body temperature
Are you cold all the time? Do you frequently have icy hands and feet?
As you decrease the amount of food you consume, your body throttles the metabolic engine to conserve the little energy you have left. While this adaptive response is associated with many health benefits, a perpetual energy deficit will lead down a frustrating road. Long-term undereating lowers thyroid output, leading to decreases in metabolic rate and body temperature.
If your hands and feet are always cold, eat more. Protein, saturated fat, carbohydrates and salt are especially helpful in raising body temperature (did someone say pizza?).
6. Chronic constipation
Fiber supplements are a mainstay in the diet industry. And it comes as no surprise in view of the chronically constipated dieter. Constipation and irregularity are telltale signs of inadequate energy intake (and substandard food choices). Decreased input = decreased output. It’s really not rocket science.
Apart from eating a nutrient-dense whole food diet, consider increasing your calories until you have bowel regularity again. I don’t care how good you think your diet is, if you hit the toilet once every 3 days you’re not eating enough. Remember, one bowel movement a day keeps the uhm… doctor away.
Rock-bottom Calorie Intake on a Diet
So how low can you go?
Your goal is to maintain a moderate negative energy balance that allows you to lose weight without compromising day-to-day performance. Never sacrifice performance and sanity for a set of six-pack abs.
Take your bodyweight in kilogram and multiply it by 22 = rock-bottom calorie intake [BW in kg x 22 | or BW in pounds x 10]. If you weigh 160 lbs your rock bottom calorie intake is 1600 calories per day –> 160 x 10 = 1600
Going lower than that will inevitably result in metabolic mal-adaptations. You don’t want to go there. Remember, even when trying to lose large amounts of weight, you need to give your body sufficient fuel to sustain metabolic integrity. Don’t focus excessively on the individual foods or macronutrient ratios (low carb vs. low fat). Instead, focus on maintaining a moderate calorie deficit over time.
I have to chuckle every time people try to tell me how hormones, micronutrients, meal timing (“no carbs past 5 PM”) and/or any other factor outweighs the importance of calories in the context of human health and performance. I have news for you nutrition hippies out there: Your hormones are built with the calories (i.e. the foods) you eat. Your vitamins and minerals come with the calories you consume (food= calories) and reducing carbs at dinner only works through the “magic” of energy balance (calories in vs. calories out).
Calories are KING!
Eat enough. Don’t overtrain. Get sufficient sleep, and your body will do what it needs to do. Yes, nutrient-density (aka food quality) matters, but let’s focus on the big picture before we get lost in the details, shall we?
Lean and Lazy
Want to know the secret to sustained fat-loss and metabolic health?
In order to get lean, you have to sustain an energy deficit for however long it takes. Eat less than your body expends until you reach the desired level of leanness. No two ways about it. But you’ll only be able to make it there in one piece if you get a little… lazy.
Eat less. Train less.
The best fat-loss results I’ve ever seen was with training no more than 3 days per week while dialing in my nutrition (calories are KING!). A higher workload inevitably results in higher energy requirements and hunger levels, making this game unnecessarily difficult.
What do you want?
Ask yourself, do you want to look and perform great on a day-to-day basis or do you want to try the next best celebrity 6-week transformation that will crush your metabolism and suck the very life out of you?
Thank you for reading
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