Cod liver oil and vitamin AD are not the same, both are more common, as they both contain vitamin A and vitamin D, thus easy to confuse, but there are certain differences between the two in the way they are made, the ingredients they contain, the requirements for use, usage, etc. 1, different ways of making: cod liver oil is extracted from the liver of deep-sea fish, which is a natural ingredient, and may have an odor. Vitamin AD often refers to vitamin AD drops (capsule type), which is a synthetic compound preparation, yellow in color and odorless; 2. Different ingredients: cod liver oil contains vitamin A, vitamin D, DHA, unsaturated fatty acids and other substances, while vitamin AD drops contain vitamin A and vitamin D, and also contain vegetable oil, vitamin E and other excipients; 3. Different use requirements: cod liver oil belongs to health food, which can be Buy it according to your needs and consume it in moderation in your daily life. Vitamin AD drops are medicines and should be used under the guidance of a doctor and not for long-term use; 4. Vitamin A and vitamin D are both essential fat-soluble vitamins, but a balanced and comprehensive diet and appropriate physical exercise in daily life can meet daily needs, you can eat more eggs, milk, animal liver, fish, meat, carrots, tomatoes, etc., in general, no additional supplementation preparations. And too much drug supplementation can accumulate in the body, which can cause toxic reactions, itchy skin, dry lips, fever, headache, vomiting, diarrhea, nausea and other manifestations, which can be life-threatening in serious cases, so the drugs should be used under the guidance of a doctor and avoid taking them blindly.