Dr Brennan Spiegel (physician, gastroenterologist, and author of Pull) and Dr Lachlan Kent (cognitive scientist and founder of Mental Gravity) explore how seasons, sunlight, serotonin, and gravity shape mood, attraction, and human connection.

Broadcasting from opposite hemispheres—Brennan in winter in Los Angeles and Lachlan in summer in Melbourne—they examine why people often feel more “down” in winter, why this is linked to reduced sunlight and serotonin, and how this helps explain the phenomenon known as “cuffing season”—the seasonal urge to pair up.

They connect dating, love, posture, breath, yoga, serotonin, oxytocin, and even planetary orbits into a single biogravitational story: human connection is shaped by the same gravitational cycles that shape the seasons themselves.

Seasons as Gravitational Cycles

Seasons arise from Earth’s orbit around the sun
Not just temperature cycles, but gravitational and light cycles

Mood follows seasonal gravity:

Summer = outward, expansive, light

Winter = inward, heavy, contracting
Breath mirrors this cycle: in/up, out/down

Winter, Serotonin, and Mental Gravity

Sunlight boosts serotonin
Low winter sunlight → lower serotonin → heavier mood
Seasonal Affective Disorder (SAD) as a gravity-related mood state
Serotonin as a “gravity management molecule” that supports:

• Muscle tone
• Circulation
• Upright posture
• Mental elevation

Love, Attraction, and Gravity

“Falling in love” uses gravitational language
Uprightness—physical, emotional, moral—is attractive
Winter dating favors depth over display
Spring favors peacocking; winter favors bonding
Long-term connection as gravitational alignment of values

Winter Practices for Gravity Resilience

Movement & Posture
Yoga as a winter-friendly anti-gravity practice
Inversions, posture, alignment, balance
Low-intensity movement over intense training

Light &Environment
Maximize sunlight exposure
Use light boxes in high-latitude winters
Get outside when possible

Diet & Chemistry
Tryptophan-rich foods: turkey, avocado, chicken, chickpeas, kidney, beans, eggs, tofu, nuts
Support serotonin production through diet

Connection
Cuddling, closeness, bonding
Oxytocin release
Oxytocin → vagus nerve → serotonin
Parasympathetic “rest and digest” state

Neurochemistry of Winter Bonding

Oxytocin primes vagus nerve
Vagus nerve regulates serotonin release
Cuddling + calm = anti-gravity physiology
Parasympathetic tone matches seasonal slowing

Biogravitational Medicine in Daily Life

Human health reflects planetary physics
Sun, moon, Earth, and orbit shape biology
Mood, love, and seasons are not mystical—just natural
Gravity as the hidden organizer of emotion, posture, and connection

Timecodes

00:00 — Welcome & hemispheres
01:15 — Seasons and gravity
02:15 — What is cuffing season?
03:15 — Mood, winter, and seasonal affect
04:40 — Sunlight, serotonin, and heaviness
06:05 — Planetary cycles and breath cycles
07:15 — Love as anti-gravity
08:15 — Depth vs display in dating
09:20 — Uprightness and attraction
10:45 — Winter activities and posture
11:35 — Yoga and winter gravity
13:15 — Balance, breath, and alignment
15:40 — Light therapy and sunlight
16:40 — Diet and serotonin foods
16:55 — Cuddling, oxytocin, vagus nerve
18:15 — Parasympathetic winter mode
19:05 — Biogravitation and planetary life
20:35 — Falling in love & falling physically
21:00 — Closing reflections

Resources

The Gravity Doctors: https://thegravitydoctors.com
Dr Brennan Spiegel: https://brennanspiegelmd.com
Dr Lachlan Kent: https://lachlankent.au
Book — Pull: How Gravity Shapes Your Body, Steadies the Mind, and Guides Our Health