Is it true that walnuts can prevent cancer?

Walnuts gives us protein,Taking walnuts as a healthy diet can reduce the heart disease and also plaque accumulation.but walnuts cannot reduce cancer.To prevent cancer must avoid using tobacco related materials ,its the better thing to do.

Walnuts have several components such as omega 3 fats, antioxidants, phytosterols and polyphenols that have been shown to reduce the risk or slow the growth of cancer. Although nuts are high in fat (and thus calories), the fatty acids in nuts are predominantly 'good' unsaturated fatty acids. Other additional components of nuts that may contribute to a reduction in heart disease and cancer risk include fibre and 'bioactive' compounds.
And also, making lifestyle changes, such as keeping a healthy body weight, limiting alcohol intake and taking regular exercise, can also help reduce cancer risk