HEART:

This vital organ of the body has to be always healthy and efficient as it is responsible for the circulation of blood. Diseased heart results in deterioration of the healthy body. This knowledge we obtained after centuries of scientific research yet it was simply told to us fourteen hundred years ago by our great Prophet (peace be upon him).
"Verily in the body there is such a piece of flesh that if it remains alright the whole body keeps well but if this piece of flesh develops some defect the whole body becomes unhealthy. Behold,- this piece of flesh - it is heart."

SIESTA:

It was the habit of our blessed Prophet to sleep for a while after lunch, his companions also followed this practice. This short nap gives relief to the vital organs of the body like heart and brain.

MODERATION IN FOOD:

Both Qur’an and Hadith have touched this topic, Qur’an tells us in the verse 30 of Surah Al Airaf:

"O children of Adam, look to your adornment of every place of worship and eat and drink but not prodigal Lo! He loveth not the prodigals."

Strenthening this order, the Prophet has strictly forbidden over eating in the following Hadith:

"It is enough to eat few morsels of food to keep one's back straight."

"If you must eat more, be sure that only one third of your stomach is filled with food, one third is left for water and the remaining one third for air."
"A Muslim eats in one intestine (stomach) whereas a nonbeliever eats in seven intestines."

It has been proved beyond doubt that over eating is the root of many diseases and also responsible for premature senility. It produces obesity, predisposes to dangerous diseases like diabetes, menitus, hypertension, coronary heart disease and paralysis.

DIABETES MELLITUS:

This is due to insulin deficiency. Overeating gets the special cells of the pancreas (islets of Langerhans) over worked so it cannot meet the increased demand for insulin. Those cells may get tired, atrophy and causes deficiency of insulin.

 PARALYSIS, CORONARY HEART DISEASE & PREMATURE SENILITY:

Their basic course is the narrowing of the coronary arteries. Paralysis is the natural result of blocking of an artery in the brain, should this happen in the heart Myocardial infection results. Premature senility is installed when majority of the arteries in the body get narrowed.

Slit in the form of cholesterol and triglycerides are deposited in the arteries. Over eating increases blood cholesterol levels. Pork and beef contain high cholesterol values while on the other hand birds have the least amount. Qur’an mentioned that birds meat is one of the specialties of Paradise.

Olive has been repeatedly mentioned in Qur’an, and statistics shows that heart attacks occur more in Northern Italy where they use butter and margarine for cooking than in Southern Italy where olive oil is generally used.

Patients suffering from narrowing of the coronary artery usually develop the heart attack after a heavy meal.

Source: islamic-world.net