Eat to Beat Disease

Li introduces the concept of angiogenesis—the process by which the body forms and maintains blood vessels—as a critical defense system against disease. Most people are unaware that microscopic cancers are present in many individuals. However, these tumors remain harmless as long as they cannot secure a blood supply through angiogenesis. When angiogenesis functions properly, the body maintains a perfect balance, providing blood flow to healthy tissues while preventing diseases like cancer from growing. Li explains that angiogenesis is key to keeping the body in homeostasis by ensuring the right amount of blood vessels are formed; he highlights how certain foods can support or inhibit this process.

Li stresses that our bodies can either enhance or disrupt angiogenesis, leading to a variety of health outcomes. For example, excessive angiogenesis can contribute to diseases like cancer, rheumatoid arthritis, and macular degeneration, while insufficient angiogenesis can lead to conditions such as neuropathy and chronic wounds. By consuming certain foods—such as soy, tomatoes, and green tea—individuals can help regulate angiogenesis and prevent disease. Li shares case studies and clinical evidence to support his claim, such as the success of antiangiogenic treatments in cancer therapy, to demonstrate the power of regulating blood vessel growth.

This chapter sets the stage for Li’s explanations about how diet can influence angiogenesis and how incorporating specific foods can help maintain the body’s natural defenses.

Li explores the vital role of stem cells in maintaining and regenerating the body’s organs and tissues. Stem cells, which originate during an individual’s earliest stages of life, are pluripotent, meaning they can transform into any type of cell. They remain essential throughout life, continuously working to repair and replace damaged or aging cells. Li explains how organs like the intestines, skin, lungs, and even the heart regenerate at different rates, highlighting the importance of stem cells in this process. Without them, the body would be unable to heal, making survival impossible after just a few weeks of life.

Li describes how stem cells are called into action during injury or disease, mobilizing from their “niches” in bone marrow and other tissues to the injured or diseased site. This process is particularly significant in heart and vascular repair, where stem cells help regenerate damaged tissue. The ability of stem cells to adapt and transform based on environmental signals underscores their unique role in health defense. However, various factors can damage stem cells, including smoking, air pollution, alcohol, and even aging, which reduce their effectiveness and numbers over time.

Stem cells are also critical in modern medicine, with treatments like bone marrow transplants saving cancer patients by restoring their immune systems. Li points out that stem cells are now being researched and applied to treat a wide range of conditions, from cardiovascular disease to neurodegenerative disorders. Remarkably, certain foods can influence stem cell performance, enhancing regeneration or protecting stem cells from damage. In the coming chapters, Li will discuss how diet can help individuals harness the regenerative power of stem cells to maintain health, recover from injury, and combat diseases like diabetes and heart disease.

Chapter 3 explores the microbiome, which is a critical and complex ecosystem of bacteria, viruses, fungi, and microorganisms living in and on the human body. This collection, comprising around 39 trillion bacteria, is crucial for maintaining health, supporting digestion, and even influencing mood and behavior. Li explains that while humans once viewed all bacteria as harmful pathogens, scientific advancements have revealed that many bacteria are beneficial and play a vital role in keeping us healthy. The microbiome helps regulate immune function, protect against diseases like diabetes, and even aids in metabolism and fat storage.

Li traces the evolutionary relationship between humans and bacteria, pointing out that human ancestors’ diets of fiber-rich plant foods nurtured beneficial bacteria in their guts. He emphasizes that diet remains a key factor in shaping the microbiome even in the present. The chapter also highlights the symbiotic relationship between humans and bacteria, noting that beneficial bacteria can produce substances—such as short-chain fatty acids (SCFAs) —that reduce inflammation, improve digestion, and support angiogenesis. Certain types of bacteria, like Lactobacillus and Bifidobacteria, are associated with these health benefits.

Li stresses the importance of nurturing the microbiome through diet, particularly by consuming foods rich in prebiotics and probiotics. Prebiotics, such as fiber, feed beneficial bacteria, while probiotics, which are found in fermented foods like yogurt and kimchi, introduce new helpful bacteria into the system. However, not all bacteria are beneficial. Some, like Desulfovibrio, can produce toxic byproducts like hydrogen sulfide, damaging the gut lining and contributing to conditions like inflammatory bowel disease.

The chapter also discusses how external factors, such as antibiotics and lifestyle choices, can disrupt the delicate balance of the microbiome. Li says that modern medicine’s growing understanding of the microbiome is opening new possibilities for treating diseases using beneficial bacteria. He highlights how focusing on a healthy diet can improve microbiome health, potentially influencing multiple defense systems in the body.

Chapter 4 focuses on DNA protection, emphasizing its vital role as a blueprint for health. DNA is constantly under attack from both internal factors (like inflammation) and external sources (such as ultraviolet radiation and toxic chemicals), resulting in tens of thousands of daily damage events. However, the body has evolved multiple defense mechanisms to repair DNA and maintain health. These mechanisms include molecular repair processes that fix structural abnormalities and epigenetic changes that turn certain genes on or off based on environmental and lifestyle factors.

Telomeres (protective caps at the ends of chromosomes) are another crucial aspect of DNA protection. They safeguard DNA from damage caused by aging; however, lifestyle choices such as diet, exercise, and sleep can influence telomere length. A healthy diet can support these defense systems, enhancing the body’s ability to repair DNA and protect telomeres from shortening.

Li also explores the history of DNA research, from Gregor Mendel’s discovery of genetic inheritance in 1866 to the sequencing of the human genome in 2003. These scientific breakthroughs have laid the foundation for understanding how DNA works to defend health. Li highlights the role of epigenetics, explaining how lifestyle factors can modify DNA activity, potentially amplifying helpful genes or suppressing harmful ones. Foods and other behaviors can epigenetically influence health by either supporting or weakening these processes.

Finally, Li touches on future possibilities for genetic treatments, including CRISPR, a revolutionary gene-editing technology that may help treat various diseases by modifying DNA. The chapter concludes by emphasizing the importance of lifestyle choices—especially diet—in protecting and repairing DNA, ensuring long-term health and resilience.

Li highlights the immune system’s role as a key health defense system, protecting against infections, cancer, and diseases. He explains that a healthy immune system is constantly on standby, prepared to identify and destroy harmful invaders, including cancer cells, before they cause damage. Sometimes, cancer cells can evade the immune system by cloaking themselves in “friendly” proteins, but new immunotherapy treatments, such as checkpoint inhibitors, can help the body unmask and eliminate cancer cells. One example is former President Jimmy Carter’s successful treatment with immunotherapy for malignant melanoma, which had spread to his liver and brain.

Li also highlights other cutting-edge immunotherapies, such as CAR-T cell therapy, which reprograms a patient’s immune cells to target specific cancers like lymphoma and leukemia. He emphasizes the immune system’s ability to be both proactive and reactive, detecting threats and swiftly mounting responses when needed. While some individuals with compromised immune systems—like those with AIDS or who take immunosuppressant drugs—are at greater risk for cancer, others can boost their immune defenses through healthy lifestyle choices.

Li says that diet plays a crucial role in immune health. He notes that certain foods contain bioactive compounds—like ellagic acid in berries and nuts—that can boost immune function, including blocking cancer cells from evading detection. Exercise, stress management, and sleep also help maintain balanced immune defenses. He concludes the chapter with a discussion of the history of immunity, from ancient techniques like variolation in China to modern vaccines, which have protected humanity from once-deadly diseases such as smallpox. The immune system’s sophisticated and adaptive mechanisms, coupled with new medical breakthroughs, offer hope for treating cancer and other diseases in the future.