I want to lose fat and gain muscle. A nutritionist said to eat more, especially carbs.

• Ciara, 28, submitted an average day of eating to be reviewed for BI's Nutrition Clinic.
• A nutritionist said eating more food, especially carbs, would help her.
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Ciara, 28, submitted her eating routine to Business Insider's Nutrition Clinic, where qualified dietitians and registered nutritionists offer readers advice on their eating habits.

She said her goals are to lose fat and gain muscle.

Ciara does five CrossFit sessions plus five cardio workout classes a week. She rests on Sundays, she said.

Sports nutritionist and personal trainer Rebecca Ward told BI that as Ciara uses so much energy, she needs to eat enough to fuel herself and help her body recover, even if she wants to lose weight.

"She would also benefit from taking a lighter training day on one of her days, rather than having only one rest day per week," Ward said.

Building muscle requires enough rest and recovery time between workouts, Ward added.

"If she's sufficiently fueled through better, more optimal food choices, that is definitely achievable," she said, referring to building muscle and losing fat.

While strength training is essential for muscle building, exercise is not a prerequisite for fat loss. Moving more does contribute to a calorie deficit, but research suggests formal exercise only makes up about five to 10% of a person's overall daily calorie expenditure.

Over-exercising without recovering sufficiently can put stress on the body, hinder progress, or be a symptom of an unhealthy relationship with exercise.

"When we overexercise we often do it for the wrong reasons, believing we 'need to sweat every day to burn calories' or we 'need train cardio to lose weight,' when actually our bodies will benefit more from a mixture of exercise regimes," personal trainer Hayley Madigan previously told BI.

Ciara eats a high-protein diet

Ciara doesn't eat until 3 p.m. when she has half a high-protein ready-meal consisting of rice and meat.

After working out, she has an egg white omelet with mushrooms, onions, and cauliflower rice; or salmon, with broccoli, and cauliflower rice.

Later in the day, she has a portion of protein pancakes, two packets of protein chips, and, if she's still hungry, a protein shake or bar.

Ciara estimates she eats 1,200 to 1,300 calories and 110 to 120 grams of protein per day.

By not eating till 3 p.m., Ciara creates a large fasting window from the evening before. While some people feel good while intermittent fasting, it doesn't suit everyone and isn't required for fat loss.

Registered dietitian Jaclyn London previously told BI she recommends people eat breakfast as it can form part of a healthy relationship with food and also "set the stage" for the day ahead.

Eat enough carbs to fuel and recover

Ward said it's great that Ciara is eating plenty of protein to help her maintain muscle mass, but she will struggle to build muscle with such low overall food intake.

"Her diet is very low in calories given the energy expenditure she will have with 10 exercise sessions a week," she said. "It will be difficult for Ciara to recover from or fuel her workouts optimally."

It's true that a calorie deficit is required for fat loss, but dropping your intake too low can have negative consequences such as slowing the metabolism, fatigue, brain fog, muscle loss, and menstrual cycle loss.

"I'd be intrigued as to how well she performs during workouts that are designed to hit her goal of increasing muscle mass," Ward said. "She would benefit from having more carbs in her diet to optimize performance in said workouts, to achieve higher intensity and volume."

Ward recommends Ciara eat more carbs with every meal and snack, perhaps starting by eating more fruit daily, which would provide fiber too.

Carbs not only provide energy for workouts but help replenish glycogen stores after exercise too, which aids recovery.

Don't forget healthy fats

Ciara's diet is also low in fat.

"Fats are essential for optimal health, are fuel for exercise at lower intensities, but also very important for recovery," Ward said. "So adding in a little oil, avocado, nuts, and seeds will help her recover from training and have greater vitality from fat-soluble vitamin absorption."

Consider separate fat-loss and muscle-gain phases

While it's not impossible to lose fat and gain muscle simultaneously, doing so in separate cycles can be more effective.

This means eating at maintenance calories or a slight surplus to fuel muscle growth for a few months, and then dropping into a slight calorie deficit to lose body fat.

"Losing fat and gaining muscle at the same time is possible, but is definitely sub-optimal and arguably better done in phases, i.e. maintenance and then a fat loss phase," Ward said. "The exercise is more enjoyable too when at maintenance calories."