Cancer Metabolism: Sugar, Fructose, Lipids & Fasting | Gary Patti | 215

Short Summary: How dietary fructose affects the growth rate of cancer.

About the guest: Gary Patti, PhD is a professor at Washington University in St. Louis, holding appointments in chemistry, medicine, and genetics

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Episode Summary: Nick Jikomes talks to Dr. Patti, exploring how cancer cells metabolize sugars like glucose and fructose, focusing on a recent study showing fructose indirectly boosts tumor growth in mice via liver-produced lipids called lysophosphatidylcholines (LPCs). The discussion covers cancer biology basics, Warburg effect, tumor microenvironments, and systemic metabolic impacts of cancer, while also touching on dietary implications, fasting, and the complexities of nutrient use in cancer progression.

Key Takeaways:

Cancer cells often rely heavily on glucose, excreting it as lactate even when oxygen is available (Warburg effect), but take up more than their mitochondria can handle.

In a study, high fructose diets accelerated tumor growth in mice by 4x, not because cancer cells use fructose directly, but because the liver converts it to LPCs, which tumors use to build membranes.

Tumors are not just cancer cells; they recruit healthy cells in their microenvironment, and their metabolic effects ripple across the entire body, altering distant tissues.

Excessive fructose consumption may worsen tumor growth, but cutting it poses little risk and could benefit cancer patients, pending human studies.

Fasting may reduce cancer initiation risk in animals, but its effect on existing tumors is less clear and could worsen wasting (cachexia) in late stages.

The body tightly regulates blood glucose via the liver, so simply cutting dietary glucose won’t starve tumors, highlighting cancer’s metabolic adaptability.

*Not medical advice.

00:00:00 Intro
00:05:35 Cancer Biology Basics
00:11:26 Tumor Initiation and Immune Evasion
00:17:13 Studying Early Cancer with Zebrafish
00:23:19 Metabolic Changes in Tumors
00:29:16 Tumor Microenvironment and Healthy Cells
00:34:28 Glucose vs. Fructose Metabolism
00:40:17 Fructose and Cancer Cell Growth
00:46:04 Fructose Processing in the Body
00:52:49 High Fructose Diets in Mice
00:59:22 Liver’s Role in Tumor Growth
01:06:06 Identifying LPCs as Key Nutrient
01:12:03 LPCs and Dietary Fat Connections
01:17:19 Fructose Intake Implications
01:23:40 Endogenous Fructose and Drugs
01:27:57 Ketogenic Diets and Cancer
01:34:09 Fasting and Cancer Risk
01:39:59 Cancer Phases and Diet Strategies