Protein is essential for the body to grow and repair itself, according to the NHS.

It’s a great source of vitamin and minerals, including iron, zinc and some B vitamins.

Eating a high-protein diet could make you feel fuller for longer, and could help muscles to recover faster after a workout.

But, how are you supposed to know when you’re not getting enough protein in your diet? These are the seven most common warning signs to look out for.

Sleep

Without enough protein, the body struggles to maintain a healthy brain.

“Your brain has the ability to control all of the hormones which are necessary for a good night’s sleep,” said Training and Nutrition Specialist, David Weiner, from Freeletics.

“When your body lacks the protein necessary to maintain a healthy brain, it can lead to a hormonal imbalance which will ultimately have an effect on your sleep.”

Hair loss

Hair is mainly made up of a protein known as keratin.

“If you’re consistently not getting enough protein, over time, you may notice your hair start to thin or even fall out,” said Weiner.

“That’s because your body stops using protein for non-essential things like hair growth in an effort to preserve its stores.”

Infections

People that haven’t had enough protein in their diet are more likely to develop infections.

That’s because protein is needed by the immune system to fight off bacteria or viruses.

“When your body does not have the right amount of protein, the number of new white blood cells decreases.

“This results in a weakened immune system and increased risk of infection.”

Food cravings

One of the first signs of protein deficiency is craving sweets, said Weiner.

“Frequent food cravings and the need to snack often in between meals can be the consequence of not enough protein and too many refined carbs, as protein evens out the highs and lows of blood sugars.

“You may crave sweet treats more than you used to, and also feel as if you’re never quite satisfied. “

Poor wound healing

Protein is required to help the body make new skin and heal existing wounds.

“Protein deficiency has shown to contribute to low wound healing rates and reduced collagen formation, according to research.

“Without adequate protein, the wound healing process is said to be greatly compromised.”

Brain fog

Carbohydrate is crucial for fuelling the brain, and eating protein helps to time-release these carbs to avoid blood sugar spikes.

Without eating enough protein, and purely relying on bread or crackers for energy, could lead to brain fog.

Low energy

Eating more protein helps to boost energy and stay motivated, said the nutrition specialist.

“A low protein diet can result in muscle wasting, fatigue and even weight gain.

“You can even find yourself working out more but seeing less results as your diet is not providing you with the adequate nutrients and giving you the energy that you need to complete a productive workout.”