These diet mistakes not only backfire, they can seriously impede your long-term progress. Here's what NOT to do.
For fat loss, the most important factors are being in a caloric deficit and consuming sufficient protein.
Quality of food matters a lot when it comes to health and feeling good. It also has a small impact on fat loss. But the truth is, if you're in a caloric deficit, you will lose fat.
But a caloric deficit doesn't necessarily mean eating less (although that's normally part of the equation). It means consuming less energy than you're USING every day. You can create a deficit by reducing food intake, increasing activity levels, or both.
Look at the two situations below:
On the left, the caloric intake is 2500 calories per day, and the energy expenditure is 3000. On the right, the caloric intake is 1500, and the energy expenditure is 2000. In both cases, the deficit is 500 calories per day. Both will lead to the same fat loss.
But consuming more calories and moving more has several advantages:
- You're more likely to maintain or even increase muscle mass.
- You're less hungry. You're eating significantly more food.
- You'll have fewer cravings. Eating more allows you to keep carbs higher. A higher carb intake minimizes cravings by preventing an excessive drop in leptin (among other things).
- You can more easily cover micronutrient needs. If you eat more, you don't simply increase macronutrients (carbs, protein, fats) but also vitamins, minerals, and fiber.
- It's more sustainable. While you can force yourself to consume super-low calories for a short period of time, it's not sustainable. That's why more than 85% of the people who lose weight regain it.
- You have a lower risk of metabolic adaptations. The decrease in metabolic rate and energy expenditure via hormonal changes – like lowered T3 levels, increased leptin, lowered testosterone and estrogen, and increased cortisol – occurs mostly in response to food deprivation.
Achieving a caloric deficit while eating plenty of food doesn't have as much of an effect. But if your deficit comes from a very large caloric restriction, all kinds of bad things can happen.
For example, the more you cut calories down, the more likely you are to lose muscle mass while dieting. But doesn't eating plenty of protein prevent that? Only to a small extent.
A lot of the protein you ingest is either turned into energy or used to produce neurotransmitters. Only around 10% of the protein you eat is used to build (or repair) muscle. Even if you increase protein by 50 grams per day, only about 5 grams will be used to repair and build muscle tissue.
Sure, a lot of the 50 grams will be used for energy – which can be muscle-sparing as there's less need to break down muscle for fuel – but that's an inefficient process. To make 1 gram of glucose to be used for fuel, you'll need 1.6 grams of amino acids converted by the liver.
In our example, if you increase protein intake by 50 grams per day, at the most, you can produce 31 grams of glucose. And since some of that protein will be sent to the muscles or to make neurotransmitters, it's likely closer to 20 to 25 grams. In other words, you'd need to increase your protein intake by a lot to be as effective as a small number of carbs.
More importantly, carbs aren't just about energy for building muscle:
- Carbs increase mTOR levels, which increase protein synthesis.
- Carbs increase IGF-1, which is highly anabolic.
- Carbs increase insulin, which isn't the devil that some make it out to be. It's quite anabolic and anti-catabolic.
- Carbs help decrease cortisol. The cortisol response to training is much higher when carbs intake is low.
The higher you can keep your carbs while dieting and training to lose fat, the more likely you are to keep your muscle mass or increase it.
I worked with an IFBB pro-bodybuilder who had used a low-carb diet with no cardio for years. His top competition weight was 176 pounds. He switched to a higher-carb approach – eating about 300 grams per day while dieting down. He also did a lot of low-intensity activity like walking. He was then able to compete at 205 pounds and was just as lean.
The bottom line? Increasing non-stressful physical activity is a better approach to getting lean than using strict food restriction.
Walking or hiking is my favorite. I advise clients to shoot for 10,000 steps a day. Basically, just try to move as much as possible throughout the day. I also recommend adding steady-state cardio or playing basketball.
Increasing caloric expenditure via hard training will have its own set of problems. Your body won't be able to recover from it. But low-stress activity is perfectly fine.
Being greedy with fat loss is even worse than being greedy with muscle gain. When you cut food intake too much, you can:
- Lose muscle mass.
- Experience metabolic adaptations that cause cravings and kill your energy.
- Kill libido.
- Make it nearly impossible to sleep because cortisol stays up chronically, which leads to high adrenaline.
- Experience nutritional deficiencies.
- Kiss your good mood goodbye.
- More easily rebound once you stop your diet.
I get it, though. You see the extra fat in the mirror and you hate it. You want it gone yesterday. You're willing to do whatever it takes to flush it out as quickly as possible.
But listen, if fat loss occurs too quickly because you cut out too much food, the consequences above won't wait long to appear. This makes it hard to reach your goal because the process quickly becomes unbearable. Or it makes it impossible to sustain the body composition you achieved.
A rate of fat loss of around 1% of your body weight per week is about right. Obviously, extremely overweight people can lose faster without suffering the consequences. But if you're a hard-training lifter looking to be ripped, 1% of your body weight per week is an adequate target. Up to 1.5% is sustainable, especially if it's achieved through a moderate food reduction and an increase in overall activity.
The more you reduce food, the more you increase your chances of bad things happening.
Consuming a caloric surplus with adequate protein is required to build muscle at a maximal rate.
Carbs are especially important because of the physiological response they elicit (increase in mTOR, IGF-1, and insulin, possibly decreasing cortisol) which facilitate muscle growth. Not to mention, carbs provide superior fuel for resistance training, leading to better performance.
A review of literature on keto dieting found that while it's adequate for weight and fat loss, it leads to inferior size and strength gains compared to carb-containing diets (1). While this review shows that keto is inferior for muscle growth and performance, it also infers that consuming carbs is important to maximize them.
Up to a point, consuming more calories and carbs will facilitate muscle growth. However, past a certain point, it will only lead to marginally more gains, if any.
For many, it's worth adding 10 or 20 pounds of fat if it allows them to gain 10 pounds of muscle. After all, gaining muscle is a lot harder than losing fat.
However, bulking can be a mistake if:
You already have a good amount of body fat.
If you're skinny, adding 15 pounds of fat to be able to pile on 10 pounds of muscle can be worth it. But if you have 20% body fat, bulking could take you up to 30% or more. At that point, not only are you looking worse despite the added muscle, but now your health will start to suffer.
If you've never successfully dieted fat off.
Personally, I have no issues with adding fat to build more muscle because I know I can diet it off. I've done it tons of times. But if you've never been through a fat loss diet and don't know if you're capable of sticking with it – or worse, if you've tried to lose fat in the past but always failed – then adding a lot of fat is a bad idea.
I'm not saying to avoid eating a surplus if you want to build muscle. That doesn't work well. But there's a difference between consuming a 300-calorie daily surplus from good foods and eating a 1500-calorie surplus by eating mostly junk.
- Valenzuela PL et al. Effects of Combining a Ketogenic Diet with Resistance Training on Body Composition, Strength, and Mechanical Power in Trained Individuals: A Narrative Review. Nutrients. 2021 Sep 1;13(9):3083. PubMed.