Foodstuffs for special dietary purposes are products that, due to their special method of preparation or composition, differ from common foodstuffs and are intended to meet the nutritional needs of specific groups of consumers, such as oncology patients. The indication for the use of these products is to provide the body with essential nutrients in the right proportions, thereby improving or maintaining the current state of health. Dietary supplements are also food products that contain vitamins and other substances, and their intake is aimed at helping to maintain specific nutrients in the human body at the appropriate level.Dietary supplements should be used under medical supervision and at a dosage determined by the body's needs. Both of the above-mentioned groups of nutritional products are gaining increasing popularity among consumers. Many of them, encouraged by the described health benefits, use and dose these products without consulting a doctor or pharmacist, often exceeding the recommended intake and even replacing a well-balanced diet, which can pose a serious health risk.These products, in combination with certain medications, can also pose a serious risk of adverse effects, especially in the elderly population taking multiple medications.Therefore, their use should be cautious, and in case of any doubts, it should be preceded by consultation with a doctor or pharmacist.