Expat health insurance customers currently experiencing cold and dark winter weather may wish to ensure they consume plenty of products containing Vitamin D.
Editor of Healthy magazine Jane Druker claimed at this time of the year, stocks of this substance in the body can be depleted.
This is because it is produced when ultraviolet rays from the sun reach the skin, triggering its synthesis.
It is not naturally present in many foods but can be artificially added to some products.
The vitamin is needed to maintain adequate levels of calcium and phosphate, which is used to ensure optimum skeletal health.
It promotes the absorption of certain minerals within the gut and without it people can end up with brittle, thin or misshapen bones.
Children can develop rickets and adults can suffer from osteomalacia if they lack it.
Ms Druker explained she consumes it daily through a spray, as this is quickly and efficiently absorbed when used underneath the tongue.
She also claimed to be a "great believer" in the eating of hot meals during the winter months, stating this is what she craves.
During this cold time of year, jacket potatoes, soups and stews are "delicious, soothing and gratifying", but they do not appeal to her when the weather is warm, the expert continued.
However, it is "not a time to overindulge in fatty foods" and substances such as carrots, leeks, potatoes, parsnips and swede were promoted by Ms Druker, who called them "wonderful root vegetables".
Fruits and nuts ought to be used as snacks, she suggested, noting individuals should make sure they eat "three healthful meals a day".
"I also believe in eating seasonally and ethically," she declared.
Men and women who are expecting to overindulge over the winter or during Christmas were recently advised to carry on exercising by personal training coach at the Laboratory Spa & Health Club Danny Saunders, who remarked it is very easy to gain weight at this time of year.