Not necessarily, it depends on which specific B vitamin.
Common B vitamins include: vitamin B2, vitamin B6, vitamin B9 (also known as folic acid), and vitamin B12.
A study comparing 6404 people with esophageal cancer and 500,000 healthy people found that both vitamin B6 and folic acid intake in food reduced the risk of esophageal cancer, with 100 mg of folic acid per day reducing the risk of esophageal cancer by 12% and 1 mg of vitamin B6 reducing the risk of esophageal cancer by 16%. However, excessive intake of vitamin B12 is associated with an increased risk of esophageal cancer, with an additional 1 mg of vitamin B12 per day increasing the risk of esophageal cancer by 2%. Although the increase is small, people with esophageal cancer and those with high-risk factors should avoid vitamin B12-fortified foods (such as powdered milk and soy milk after addition).
It is important to emphasize that all references in the study were to dietary vitamin B. There is no evidence yet on the safety and efficacy of drug-derived vitamin B. Vitamin B6 is more abundant in a variety of nuts, bananas, corn, potatoes, brown rice, and chicken breast; folic acid is more abundant in spinach, mushrooms, kiwi, animal liver, and eggs, which are recommended for patients with esophageal cancer.