I am currently looking for software that can accurately provide bilingual subtitles. In the meantime, I will post the English translation of the video transcript in the pinned comment to help friends outside the Chinese-speaking world understand the content of the video. Thank you again for your support and for watching. 給需要雙語字幕的朋友:很抱歉,目前正在尋找能夠更精確上雙語字幕的軟體,在那之前我會把影片字幕逐字稿的英文翻譯放在置頂留言,方便中文世界以外的朋友理解影片的內容。再次感謝大家的支持跟收看。 Decreased appetite and poor digestion are common issues that many cancer patients face while battling their illness. At such times, nutritional supplements, as a convenient alternative, indeed solve the problem of nutrient intake for many patients. Indeed, the lack of certain key nutrients can have long-term and adverse effects on patients. Conversely, in recent decades, substantial medical evidence has accumulated showing that some specific nutritional supplements may not only increase cancer risk in the general population but also have adverse effects on cancer patients. These effects can range from worsening symptoms and lowering quality of life to triggering disease relapse and even increasing mortality. If taken in excess unknowingly, it can truly be counterproductive. So today, I will discuss three nutritional supplements that should not be consumed in excess. I hope this helps you make better choices in selecting supplements that truly boost your immunity without harming your wallet or your health. First Nutritional Supplement to Avoid in Excess: Beta-Carotene Beta-carotene is a type of carotenoid, a pigment found in yellow and orange plants. If you remember, there is a substance called triterpene in reishi and antrodia mushrooms. Chemically, carotenoids are a type of tetraterpene. Beta-carotene helps plants with photosynthesis, forms protective pigments, and assists in synthesizing their own hormones. In humans, it acts as an antioxidant and is a precursor to vitamin A, so beta-carotene is also known as a vitamin A precursor. A large meta-analysis led by the Norwegian University of Science and Technology in 2018 combined data from 69 studies and found that those who consumed the most carotenoids from fruits and vegetables had a significantly lower risk of cardiovascular disease and cancer-related mortality. However, it’s important to note that this was from food sources, not supplements. Other smaller studies have shown that higher intake of carotenoids from food is associated with a reduced risk of cervical cancer and increased survival rates in breast cancer patients. So, what about taking nutritional supplements? Research results are mixed, but most lean towards negative outcomes. Not only are the results unfavorable, but the consequences can be quite severe. For example, a study published in 2022 in the American Journal of Internal Medicine found that regular supplementation of beta-carotene increases the risk of lung cancer by 20% in adults. More crucial evidence comes from the ATBC study in Finland, a double-blind controlled trial, which found that smokers who took beta-carotene supplements had a 22% to 31% increased risk of lung cancer. For cancer patients already undergoing treatment, a study on head and neck cancer patients found that those who continued smoking and took more than 30 mg of beta-carotene daily had more than double the risk of cancer recurrence and more than triple the risk of death. Radiation therapy is an effective treatment for head and neck cancer, but when combined with smoking and beta-carotene supplementation, its efficacy is significantly diminished. In conclusion, beta-carotene supplementation is very detrimental for cancer prevention or management, especially when combined with smoking, which amplifies its harmful effects. However, don’t assume that non-smokers can safely take beta-carotene supplements. More in-depth studies show that beta-carotene can stimulate new blood vessel formation around cancer cells and promote more vigorous division of pancreatic and lung cancer cells in laboratory settings. In other words, regardless of smoking status or cancer presence, I do not recommend beta-carotene supplementation, especially in doses exceeding 20 mg daily. On the other hand, consuming beta-carotene from fruits and vegetables is completely safe and beneficial. Second Nutritional Supplement to Avoid in Excess: Vitamin B12 Vitamin B12 is the last member of the B vitamin family but is crucial for health. Vitamin B12 is essential for DNA synthesis at the beginning of life. It plays a key role in producing blood cells in the bone marrow and is necessary for the proper functioning of the nervous system, mitochondria, and metabolic processes. Vitamin B12 sources primarily include meat, dairy, and eggs, with fewer plant-based sources, mostly in mushrooms and algae. Therefore, strict vegetarians and those who do not consume dairy or eggs are at risk of B12 deficiency. Vitamin B12 is unique in that its absorption process is complex. Most trace nutrients are absorbed directly through the intestinal lining after being transported to the small intestine, but B12 cannot pass through the stomach alone due to its vulnerability to stomach acid. Moreover, it cannot be directly absorbed by the intestinal lining; it requires specific proteins for absorption. The body has prepared four 'receptionists' to handle B12: haptocorrin, pepsin, gastric acid, and intrinsic factor. Initially, B12 binds with haptocorrin in saliva to protect it from stomach acid. In the stomach, pepsin and gastric acid separate B12 from haptocorrin, and B12 then binds with intrinsic factor, which facilitates its absorption in the small intestine. Conditions affecting these four 'receptionists,' such as stomach diseases, surgery, or acid-reducing medications, can impact B12 absorption. Given the complexity of its absorption and the significant health impacts of deficiency, B12 supplementation is widespread, available over-the-counter and by prescription. However, excessive B12 supplementation is not without risks. A 2024 study with over 90,000 participants found that for every 100 pmol/L increase in blood B12 concentration, adult mortality increased by 4%, and by 6% in the elderly. Additionally, a 2017 study published in the Journal of Clinical Oncology (JCO) found that long-term B12 supplementation in men increased the risk of lung cancer by 40%, with a higher risk of up to 100% for those taking more than 55 mcg daily. Breast cancer patients undergoing chemotherapy who took high doses of B12 supplements had an 83% increased risk of disease recurrence and more than a 100% increased risk of death. It is important to note that these negative findings pertain to supplements. Studies have shown that dietary B12 from food does not carry the same risks, reinforcing that natural sources are generally safer. For strict vegetarians, individuals with stomach issues, or those on acid-reducing medications, appropriate B12 supplementation is necessary to prevent deficiency and related health issues. In such cases, regular blood tests to monitor B12 levels are recommended. Third Nutritional Supplement to Avoid in Excess: Vitamin E Vitamin E is a fat-soluble antioxidant vitamin. Antioxidants not only perform necessary physiological functions but also have the ability to donate electrons to free radicals, stabilizing them and preventing damage to important molecules like proteins, fatty acids, and DNA. This protects against cellular damage and cancer development. Vitamin E, along with vitamin C, copper, zinc, selenium, carotenoids, and polyphenols, acts as an antioxidant. However, despite its antioxidant properties, vitamin E can be harmful. It can interfere with the DNA's ability to suppress cancer-related genes, such as the well-known P53 gene, which is crucial for preventing cancer cell development. A January 2004 Cochrane review found that regular vitamin E supplementation increased the risk of gastrointestinal cancers. Another analysis published in the American Journal of Respiratory and Critical Care Medicine in 2008 showed that daily intake of 100 mg of vitamin E increased the risk of lung cancer by 5%, with higher intake leading to greater risks. The SELECT randomized controlled trial revealed that men taking 400 IU of vitamin E daily had a 17% increased risk of prostate cancer after seven years. It is important to note that these findings are specific to supplements. Consuming vitamin E from natural sources such as nuts, seeds, and dark green vegetables does not carry the same risks. Studies have found that dietary vitamin E reduces the risk of various cancers, including lung and liver cancer. In summary, these three supplements-beta-carotene, vitamin B12, and vitamin E-should be avoided or used cautiously to prevent adverse effects. Natural sources of these nutrients are generally safer and more beneficial. I hope this information helps you make informed decisions when choosing supplements. Thank you for watching, and special thanks to our supporting members. Wishing everyone a happy Mid-Autumn Festival with a full moon and family reunions. See you next time. Bye!
很喜歡你的channel 中英對照,尤其是英文那部份,有 brief descriptions and hyperlinks to relevant medical reseach, and also your written translation at the above to your video 我看文字比較快,尤其是英文,先看然後聽醫師你講解,感覺很好。謝謝!🙏
請問張醫師有聽過美國藥廠Metagenics生產的植物多種維生素PhytoMulti Capsules嗎?我因肺腺癌正在服用鏢靶藥第二代妥復克。朋友介紹,我每天也吃一顆上述植物性維生素膠囊,看了您的影片,擔心結果是反面的,會讓癌細胞活躍。另外想請問這與我的血液C E A檢查高數值87有關嗎?(先說明我對妥復克沒有抗藥性,正子篩檢也沒有其他癌變。)謝謝您耐心看完我的提問。