In the second part with Prof. Satchidananda (Satchin) Panda (Regulatory Biology Laboratory at the Salk Institute for Biological Studies in La Jolla, California), we continue talking about breakthrough discoveries from past years of him and other chronobiologists. First, we discuss how the timing of medication intake could help in optimizing its effects. Then, Satchin shares his perspective on ongoing developments in the lighting industry since the discovery of the blue-light sensitive melanopsin. In both contexts, we also discuss self-limiting features of chronobiology and circadian rhythms research that may stand in the way of using chronobiological principles to achieve policy changes in clinical practice and that should ideally be overcome to collaborate better with other medical disciplines as well as the industry. Lastly, Satchin shares his simple way of measuring scientific success.

Chapters:

(00:01:14) Intro

(00:03:00) Timing medicines

(00:08:18) Self-limiting features of chronobiology

(00:15:56) Wearable technologies and chronobiology

(00:20:22) More engagement with other disciplines

(00:29:00) Daylight-mimicking electric light

(00:34:04) Funny anecdote

(00:37:45) How to measure scientific success?

(00:41:07) Satchin’s book and podcast

(00:45:09) Outro

Studies that Satchin refers to:

John Hogenesch timing of drugs paper:

“Dosing time matters”

https://doi.org/10.1126/science.aax7621

“Clocks, cancer, and chronochemotherapy”

https://doi.org/10.1126/science.abb0738

“Could a good night's sleep improve COVID-19 vaccine efficacy?”

https://doi.org/10.1016/S2213-2600(21)00126-0

“Biological rhythms in COVID-19 vaccine effectiveness in an observational cohort study of1.5 million patients”

https://doi.org/10.1172/JCI167339

Timing of pain medication intake at evening or bedtime to manage pain in the morning:

“Bedtime Single-Dose Prednisolone in Clinically Stable Rheumatoid Arthritis Patients”

https://doi.org/10.5402/2012/637204

TRF increases the robustness and numbers of genes that cycle:

“Time of feeding and the intrinsic circadian clock drive rhythms in hepatic gene expression”

https://doi.org/10.1073/pnas.0909591106

“Diurnal transcriptome landscape of a multi-tissue response to time-restricted feeding in mammals”

https://doi.org/10.1016/j.cmet.2022.12.006

CRY double knockout mice still have metabolic rhythms upon TRF:

“Time-Restricted Feeding Prevents Obesity and Metabolic Syndrome in Mice Lacking a Circadian Clock”

https://doi.org/10.1016/j.cmet.2018.08.004

“A Free-Choice High-Fat High-Sugar Diet Alters Day–Night Per2 Gene Expression in Reward-Related Brain Areas in Rats”

https://doi.org/10.3389/fendo.2018.00154

“Repeated exposures to daytime bright light increase nocturnal melatonin rise and maintain circadian phase in young subjects under fixed sleep schedule”

https://doi.org/10.1152/ajpregu.00211.2006

“Bright light exposure during the daytime affects circadian rhythms of urinary melatonin and salivary immunoglobulin A”

https://doi.org/10.3109/07420529909116864

“Positive effect of daylight exposure on nocturnal urinary melatonin excretion in the elderly: A cross‑sectional analysis of the HEIJO‑KYO study”

https://doi.org/10.1210/jc.2012-1873

Satchin’s melanopsin discovery paper:

“Melanopsin (Opn4) Requirement for Normal Light-Induced Circadian Phase Shifting”

https://doi.org/10.1126/science.1076848

The Economist article “Light therapeutics”:

https://www.economist.com/1843/2014/12/29/the-light-therapeutic?utm_campaign=shared_article

Amandine Chaix paper that TRF is both preventative and therapeutic, 5 days TRF and 2 days not:

“Time-restricted feeding is a preventative and therapeutic intervention against diverse nutritional challenges”

https://doi.org/10.1016/j.cmet.2014.11.001

Satchin’s resources:

His book: “The Circadian Code”

His podcast: “Performance around the clock” (also on Spotify)

“MyCircadianClock” app

Panda Lab homepage: ⁠https://panda.salk.edu/⁠

As the third spotlight for the European Biological Rhythms Society (EBRS) congress, taking place in Luebeck in Northern Germany from the 24th to 28th of August 2025, Prof. Satchidananda (Satchin) Panda (Regulatory Biology Laboratory at the Salk Institute for Biological Studies in La Jolla, California) talks about several breakthrough discoveries from past years of him and other chronobiologists. In this first part, Satchin explains the relevance of time-restricted eating (TRE) with people nowadays eating around the clock and how he faced a lot of pushback from the nutrition field after his initial discovery of TRE's health benefits in mice. We discuss how food photos eventually helped him move forward with his research. He also tells us about his memories from attending previous EBRS congresses and why you should join this year. Lastly, Satchin shares some rather unique advice for early-career researchers.

Chapters:

(0:00:40) Intro

(0:05:52) Satchin Panda

(0:09:03) People eat around the clock

(0:20:35) Analyzing food photos

(0:30:59) Is late eating or reduced fasting the problem?

(0:44:00) Diurnal changes in glucose tolerance

(0:49:07) EBRS congress memories

(0:56:57) Advice for early-career researchers

(1:05:48) Outro & Teaser to Part 2

Studies that Satchin refers to:

Time-Restricted Feeding without Reducing Caloric Intake Prevents Metabolic Diseases in Mice Fed a High-Fat Diet (Hatori et al. 2012)

https://www.sciencedirect.com/science/article/pii/S1550413112001891

A Smartphone App Reveals Erratic Diurnal Eating Patterns in Humans that Can Be Modulated for Health Benefits (Gill & Panda 2015)

https://pubmed.ncbi.nlm.nih.gov/26411343/

Feasibility of time-restricted eating and impacts on cardiometabolic health in 24-h shift workers: The Healthy Heroes randomized control trial (Manoogian et al. 2022)

https://doi.org/10.1016/j.cmet.2022.08.018

Satchin’s resources:

His book: “The Circadian Code”

His podcast: “Performance around the clock” (also on Spotify)

“MyCircadianClock” app

Panda Lab homepage: https://panda.salk.edu/