Why does the immune system kill some cancer cells but misses others?Your body is creating cancer cells all the time, and if you're healthy and your immune system is healthy, it will take care of those cancer cells.

Certain foods and behaviors, however, will allow the immune system to kill some cancer cells but miss others.

Sugar is a huge culprit, as are constant stress, lack of exercise and lack of sleep. 

Immunotherapy is an approach to battle the potential risk of cancer, in which you strengthen your immune system to its full capacity. 

Christine Horner, MD, has dedicated many years of her work to researching the benefits and practices of immunotherapy.

She joins Andrea and Lisa to share tactics that will significantly lower the risk of cancers for both men and women and/or increase chances of survival after being diagnosed:

1) Spice it Up: The top immune boosting, cancer-fighting spices include: garlic (the organosulfar chemical compound that causes eye-tearing has immune-strengthening and anti-carcinogenic qualities), ginger (slice it and steep it as a hot tea to decrease both nausea and cancer risks), cayenne pepper (contains the antioxidant capsaicin that stifles and kills the growth of prostate cancer cells) and turmeric (that contains curcumin and is known to choke cancer cells to death and may be one of the most potent anti-inflammatories identified to this day).

2) Veg it Up: The top immune boosting, cancer-fighting veggies include: kale (a cruciferous vegetable that contain isothiocyanates, phytochemicals that help break down potential carcinogens and indole-3-carbidol (I3C), which helps prevent estrogen driven cancers), mushrooms (contain compounds that attack cancerous cells and prevent them from multiplying while boosting immune activity and stimulating the body's natural production of interferon; AHCC is a natural substance extracted from certain species of medicinal mushrooms and the leading alternative cancer treatment used in hundreds of clinics throughout Asia; AHCC maintains peak natural killer cell activity as proven in 25 human clinical studies) and sweet potatoes (an important carotenoid, rich in vitamin A, that has shown to lower the risk of breast cancer in women who have higher levels in their bloodstream).

3) Bug it Up: Without the beneficial bacteria found in probiotics, yogurt or kefir, our defenses are greatly weakened, allowing disease to take hold more easily. Fermented foods are another great source of beneficial immune-boosting bacteria, for example fermented tea from Japan called kombucha, made with mushrooms and a "symbiotic 'colony' of bacteria and yeast" can be beneficial in stimulating the immune system.

4) Feel it Up: Science proves the hugs and simple massages can also boost the immune system, so couples should get touchy feely for cancer prevention. Research from Carnegie Mellon University shows that those who receive more hugs are somewhat more protected from infection.

5) Laugh it Up: In the same way that grief and anger can suppress your immune system, research shows that laughter strengthens your immunity. Laughing significantly reduces cortisol levels while increasing antibodies that fight infection and cyotokines that regulate immune function and natural killer cells that seek out and destroy viral and tumor cells.