I want to build muscle and lose fat. A dietitian said to eat leaner meats and more fruit and vegetables.

• A 38-year-old man submitted an average day of eating to be reviewed for Insider's Nutrition Clinic.
• A dietitian said to eat more lean protein sources, fruit, and vegetables.
• If you'd like to have your diet reviewed by an expert, fill out this form.

Sean, 38, submitted his eating routine to Insider's Nutrition Clinic, where qualified dietitians and registered nutritionists offer advice on readers' eating habits.

He told Business Insider his goals were to build muscle and lose fat. Sean said he has been living a sedentary lifestyle but has just started exercising.

Eat protein at every meal

For breakfast, Sean tends to eat sausage, eggs, bacon, and bagels, he said.

Registered dietitian and personal trainer Kara Mockler told BI it's good that he's eating three meals per day, all of which provide quality protein and carbohydrates.

"It's beneficial to eat protein multiple times throughout the day because it ensures that your body has amino acids to use for recovery, repair, and rebuilding all day," Mockler said. "It encourages muscle protein synthesis which supports muscle growth."

Eat colorful fruits and vegetables

For lunch, Sean typically has a sandwich or a hamburger, he said.

Mockler said that Sean's diet could do with more color. She recommended Sean add one to two more servings each of fruit and vegetables per day.

"More color (fruits and veggies) ensures he's getting enough fiber (along with choosing wholegrain carbohydrate options) and vitamins and minerals," Mockler said.

Swap fatty meats for leaner protein sources

For dinner, Sean often eats steak with mashed potatoes and a vegetable.

Mockler said it's great that Sean gets a vegetable in at dinner, but he should keep an eye on his saturated fat intake.

"With sausage, bacon, hamburger, and steak all listed in the same day, if he's not careful of his portions and cuts (leanness) of those meats, he could be consuming too much saturated fat and total fat for his needs," Mockler said.

She encouraged Sean to choose the leanest options of hamburger and steak, and limit his intake of processed meat, such as sausages and bacon, to a couple of times per week.

Focus on fat loss or muscle gain for a few months

Alongside the diet tweaks, Mockler said Sean should make sure he's training correctly as this will be key in achieving body recomposition (simultaneous fat loss and muscle gain).

"A tell-tale sign of this is if the scale isn't changing much, but measurements (for example, waist and hips) are decreasing," Mockler said via email. "Sean is also likely to experience what we call 'newbie gains' as he leaves his sedentary lifestyle for one with lifting."

Strength training with progressive overload is key for fat loss, muscle gain, or aiming for both, and Mockler recommended trying to do three full-body workouts a week if possible. To hit all the major muscle groups, Sean should make sure he's doing push (chest), pull (back), squat (quads and glutes), and hinge (hamstrings and glutes) movements in each workout, she said.

"While recomposition is wonderful, it's not guaranteed," Mockler said. "Most people could benefit from choosing one goal, either fat loss or muscle gain, and committing to that for a few months."

Which one Sean starts with may depend on his current weight and body fat percentage, Mockler said. To focus on fat loss, Sean would need to eat in a calorie deficit, versus a surplus to focus on muscle building.

"Both of those phases should be paired with resistance training so that Sean doesn't lose muscle in a deficit and to ensure the extra calories are going to building muscle (versus fat gain) in a surplus," she said.