The Almighty says: "And He it is Who has subjected the sea (to you), that you eat thereof fresh tender meat (ie fish), ... This is a new study confirming that all kinds of fish have substances that prevent dementia and other diseases like Cardiovascular system disorders and some inflammations, let us read ...... The Almighty says: "And He it is Who has subjected the sea (to you), that you eat thereof fresh tender meat (ie fish), and that you bring forth out of it ornaments to wear. And you see the ships ploughing through it, that you may seek (thus) of His Bounty (by transporting the goods from place to place) and that you may be grateful "(14: Al Nahl). The world of the seas is full of secrets, and Allah, the Exalted, Had subjected the fishes of the sea for us as diet and remedy! The result of new study conducted in Finland was published in Neurology Magazine issued by the American Academy of Neurology. These results showed that intake of tuna fish plus other types of fish can limit the risks of dementia in old people. The study was done on 3600 men and women not younger than 65 years old, the results of which had shown that old people who eat tuna or other types of fishes, that are rich in omega-3 fatty acids, at least three times weekly had 26% lower risk of the incidence of brain tissue scars leading to dementia and brain clots when compared to old people who do not eat fish regularly. The same study also concluded that intake of this type of omega-3 rich fish once a week results in lowering the risk of brain clots and tissue scars incidence by 13%. At the beginning of the study, radiation scanning was done to the participants to detect the presence of any scars not causing any symptoms but may cause regression in intellectual abilities or dementia or more serious brain strokes. Five years later, the same tests were repeated, the participants answered questions in forms related to their dietary habits and if they have fish in their diet. Eriki Virtanen, from Quobio university in Finland, verified that intake of tuna or any other fatty acids rich fish can have prophylactic effects from dementia and brain strokes, while people having fried fish regularly had not these effects recorded. Fish are among the creatures which Allah, all praises to him, Had subjected to us as a food and a remedy, many studies verified that consumption of fish has medical benefits related to the treatment of memory loss and many other diseases. In front of these benefits we have to memorize Allah's mercy when He subjected this tender fish to us, He the Exalted says: "And the two seas (kinds of water) are not alike: this is palatable, sweet and pleasant to drink, and that is salt and bitter. And from them both you eat fresh tender meat (fish), and derive the ornaments that you wear. And you see the ships cleaving (the sea-water as they sail through it), that you may seek of His Bounty, and that you may give thanks "(12: Fair). Virtanen added that omega-3 fatty acids in fish play significant role in these beneficial prophylactic effects and further research should be carried on to know the effects of oils rich fish plus other important aspects. Previous studies revealed that omega-3 fatty acids have anti-inflammatory properties and they are associated in lowering the risk of cardiovascular diseases. Besides tuna fish, you can have omega-3 fatty acids from salmon, sardine, anchovy and herring fish in addition to other foods like walnut. Another study verified the importance of fish in preventing strokes. Finally, the benefits that Allah bestowed in fish, make us feel his mercy upon us and that He Had subdued everything for our benefits as manifested in the following noble verse: "And if you would count the favours of Allâh, never could you be able to count them. Truly! Allâh is Oft-Forgiving, Most Merciful "(18: Al Nahl).