Experts have highlighted a number of nutritional factors that influence our muscle mass and strength as we age.

A healthy, balanced diet is important throughout our lifetime, but changes may need to be made as we get older to counter the ageing process.

A common problem as we age is gradual loss of muscle mass or 'sarcopenia', which is a major risk factor for disability among older people.

Maintaining strong muscles is important for falls prevention and sarcopenia is associated with an increased risk of injuries and fractures.

A recent review by the working group of the International Osteoporosis Foundation (IOF) looked at published research from around the world, focusing on the nutritional factors that help to preserve muscle mass, strength and performance as we age.

Their conclusions are now published in the journal Osteoporosis International and could help people to prevent loss of muscle mass in their senior years.

Co-author Professor Jean-Philippe Bonjour, professor of medicine at the University of Geneva's Service of Bone Diseases, said that resistance training is the most obvious intervention against sarcopenia.

But he emphasised that adequate nutritional intake is also a "very important" element of any strategy aimed at preserving muscle mass and strength during ageing.

The researchers highlighted the importance of a good intake of protein, recommending an intake of 1.0 to 1.2g per kg of body weight per day to maintain skeletal muscle and bone health in older people.

A balance needs to be struck between acid-producing nutrients, such as meat and cereal grains, and alkalising fruits and vegetables.

Too much of the former can be harmful if a person does not have plenty of fruit and vegetables in their daily diet.

The researchers also emphasised the importance of maintaining adequate levels of vitamin D inside the body.

Our primary source of vitamin D comes from inside the body, where the vitamin is manufactured in response to exposure to sunlight.

But many older people do not go outdoors enough and are unable to manufacture enough vitamin D.

In light of this, a high-quality vitamin D supplement - such as the one supplied by The Really Healthy Company - is recommended for older people, particularly those who are institutionalised.

Dr Ambrish Mithal, head of the endocrinology and diabetes division at Medanta in New Delhi and another of the review co-authors, said that measures to prevent sarcopenia must be included in strategies to reduce the number of falls and fractures within ageing populations.

He concluded: "At present, the available evidence suggests that combining resistance training with optimal nutritional status has a synergistic effect in preventing and treating sarcopenia.