According to the American gastroenterologist Saurabh Sethi, the appearance of bruises with a slight impact on the skin may be the result of a lack of vitamins C and K1 in the body. This is reported by the Daily Mail. The doctor specified that vitamin C (ascorbic acid) plays a key role not only in strengthening the immune system, but also in the production of collagen - a protein that maintains the structure of the skin, bones, muscles and other connective tissues. Vitamin C deficiency weakens blood vessels, which leads to bruising on the body. The most severe form of vitamin C deficiency is known to be scurvy. Typical symptoms of scurvy include inflammatory gum lesions, swelling, small pitting and large hemorrhages mainly on the lower limbs, muscle and bone pain, and depression. Sethi added that citrus fruits, peppers, broccoli, pineapple, kiwi and leafy greens can help make up for vitamin C deficiency. However, one should consume these foods in reasonable quantities. Excess ascorbic acid and collagen can lead to kidney stones, headaches and fatigue. Bruising on the body can also indicate a deficiency of vitamin K1, which is important for blood clotting. A deficiency of this substance increases the risk of ruptured capillaries and other small blood vessels, leading to subcutaneous bleeding.