Breath volatilome: smelling the microbiome

Broadcast from KSQD, Santa Cruz on 1-29-2026:

• An emailer asks about hemorrhoids affecting 2 relatives,a 60-year-old man and his 20-year-old daughter, with the daughter also experiencing constipation worsened by fiber supplements. Dr. Dawn explains hemorrhoids are essentially varicose veins of the anus, with 102 genetic regions identified affecting blood vessel and smooth muscle strength. She emphasizes that fiber supplements without adequate water create "cement in the pipe"—recommending 16-24 ounces of water with supplements and 2 liters of clear water daily. Miralax also requires sufficient hydration to work. Key strategies include exercise to stimulate gut motility, staying off the toilet if unable to produce results, using a standing desk to reduce prolonged sitting pressure, and triggering the gastrocolic reflex by eating.
• Dr. Dawn discusses research on the "volatilome"—volatile organic compounds in breath that reflect gut microbiome composition. Researchers using sterile mice colonized with specific bacteria could identify bacterial fingerprints through breath analysis. The technique identified disease-associated compounds for tuberculosis and malaria, and correlated specific gut bacteria with asthma severity in children. The research suggests breath testing could eventually replace stool samples for microbiome assessment and disease screening.
• She explains detoxification biochemistry, distinguishing between water-soluble toxins easily filtered by kidneys and fat-soluble toxins requiring liver transformation. Phase one converts fat-soluble molecules into reactive intermediates—dangerous if they linger—while phase two attaches water-soluble molecules like glutathione to neutralize them for excretion. Supporting phase two requires green tea, cruciferous vegetables, garlic, and curcumin. She cautions against extended fasting for detox, especially over age 50, as it depletes the body's detoxification resources and muscle mass.
• A caller asks about alkaline versus acidic water. Dr. Dawn explains you cannot alkalinize blood since kidneys maintain pH, but alkaline urine is beneficial. Rather than expensive alkaline waters, adding a pinch of baking soda achieves the same effect. Eating a 3:1 ratio of fruits, vegetables, and grains to animal products naturally alkalinizes urine. She notes lemons paradoxically alkalinize because kidneys overcompensate for the acid load.
• A caller asks about managing heart disease after receiving a third stent. Dr. Dawn recommends the Mediterranean diet over DASH for cardiac patients, as Mediterranean emphasizes fish, whole grains, and fiber that binds cholesterol for excretion, while DASH focuses on calcium for hypertension. She encourages exploring exercise options through meetup.com groups and the hospital's lifestyle center, emphasizing that consistent effort can reduce biological age by 3-5 years regardless of chronological age.