The uniqueness of blood cancers is a significant proportion of them happen in children. That means most of the habits you mentioned are not going to be a risk factor in these little ones. We as Hematologist’s have determined a lot of gene changes to be a reason for the blood cancers, but the exact reason why it happens in a few is still largely unanswered. But maintaining good hygiene, enough sleep, mild exercise and healthy food habits definitely will help in prevention. More than prevention it helps a person tolerate therapy to such diseases and ultimately end up a win over cancer. As a Hematologist and Bone marrow transplant physician, I can assure you there are innumerable number of researches and new drugs are available for blood cancers now which has made a big change to outcome of most of them. Many patients are able to live a normal life with good control of cancer. Don’t get worried much.

Blood has different types of cells which undergo constant division.genetic mutations if any, lead to uncontrolled divisions leading to blood cancer. Exposure to certain chemical like benzene and formaldehyde , smoking, radiation therapy are some of the other causes or risk factors

Its an unfortunate that unlike solid organ cancers where somehow we know underlying cause, in liquid organ cancers like blood cancer in moa tof time we don't know direct cause. However there are certain genetic defects which are known to have an increased risk of blood cancers. Aquired risk factors  are - patient having connective tisise disorders, taking immunosuppressive therapy   , received prior chemo or radio therapy, exposed to certain toxins in food or adulterated food .  Veg or non veg, or obesity are not linked with ood cancer as a cause.  Keeping ourself fit - menatally, physically and financialy ( good medical insurance) are preventinve steps.