You may ask your grandparents to eat well-cooked meat, as a study has recently warned that eating steak rare (beef steak) prevents senior citizens from absorbing all the proteins that they need.
Elderly volunteers took in far fewer key amino acids - building blocks for protein - when the meat was under-cooked, compared to when they ate well-done steaks.
The digestive systems in older people struggle to break down the protein.
Researchers from the French National Institute for Agricultural Research and Clermont-Ferrand University Hospital, France stated that young people are able to digest rare and well done meat in the same way. However, the digestive systems in older people struggle to break down protein in rare meat.
Protein is crucial for building, maintaining and replacing muscles, heart and lungs.
The researchers explained that getting enough macronutrients as one gets older is important to prevent muscle loss, which is a normal part of the ageing process.
They analysed 10 elderly volunteers aged 70-82 years.
On different occasions, the volunteers ate steak that was cooked rare; on other days, they had a steak that was well-done.
After blood tests on the volunteers, the findings indicated that in view to preventing sarcopenia (the degenerative loss of muscle mass) the elderly people should be advised to prefer the consumption of well-cooked meat.
Previous research suggested that eating more protein when you are older could help prevent a stroke.
The researchers estimated that if everyone started eating more protein there could be 1,500,000 fewer stroke deaths per year worldwide.
The research appears in the American Journal of Clinical Nutrition.