Personalizing Your GLP-1 (And Where Gut Health Fits In)
You’ve started GLP-1 / GIP therapy. Food noise is quieter. Weight is moving. Now you’re hearing about “personalization”:
“Should I add glycine? L-carnitine? Both? Neither?”
Let’s simplify.
Glycine: The Calming, Sleep-Supportive Add-On
Glycine is a single amino acid that:
- Supports deep sleep by lowering core body temperature and activating your parasympathetic (rest-and-digest) system
- Helps reduce inflammation
- Is a major component of collagen (skin, joints, connective tissue)
- Can support healthier blood sugar and cravings
Who tends to love glycine:
- Women with poor sleep, racing minds at night, or frequent wake-ups
- Those with a lot of generalized inflammation and soreness
- People at the start of their GLP-1 journey who are inflamed, exhausted, and trying to stabilize blood sugar
L-Carnitine: The Energy & Fat-Utilization Support
L-carnitine:
- Helps shuttle fatty acids into mitochondria to be burned as fuel
- Supports energy production (ATP)
- May reduce delayed onset muscle soreness (DOMS)
- Helps your body use thyroid hormone (T3) more efficiently
Who tends to love L-carnitine:
- Women who want more energy for training
- Those focusing on body recompositing (losing fat, keeping/building muscle)
- People further along in their GLP-1 journey who’ve already calmed initial inflammation and now want performance
How Gut Health Influences Both
Your gut:
- Determines how well you absorb glycine and carnitine from food or supplements
- Impacts inflammation, which both glycine and GLP-1s aim to lower
- Influences energy via nutrient absorption and microbiome-generated metabolites
If your gut is inflamed, constipated, or swinging between diarrhea and bloat, you’re leaving results on the table.
Layer in:
- A consistent bowel routine (aim for 1–2 formed BMs daily)
- Enough magnesium, fluids, and fiber for motility
- A trial of eliminating a known trigger food (like gluten, dairy, or alcohol) and watching symptoms
Then, adding glycine or L-carnitine makes more sense and has a better foundation to land on.
Which One Should You Choose?
You can use this simple decision guide:
- “I’m not sleeping, my joints hurt, my blood sugar is a mess” → start with glycine
- “I’m further along, weight is down, I want more energy and fat-burning capacity” → consider L-carnitine
Both can be powerful when layered thoughtfully with:
- GLP-1 therapy
- Gut-supportive nutrition
- Strength training and movement
- Adequate protein
Personalization isn’t about collecting more vials. It’s about matching tools to your physiology and goals.
About
Mary Catalogna
Author
Mary Catalogna is a Functional Diagnostic Nutrition Practitioner, certified health coach, fermentationist, and endurance athlete who helps high-achieving women over 45 lose stubborn weight, restore energy, and feel powerful in their bodies again—without extreme diets or burnout. Mary specializes in gut health, hormones, peptides, and performance, working primarily with driven professional moms, endurance athletes, and triathletes who refuse to settle for “fine.” Her approach targets the real root causes behind weight gain, belly bloat, poor sleep, inflammation, and low energy by restoring the gut–brain–hormone connection. As an Ironman finisher herself, Mary blends lived athletic experience with deep clinical insight. She’s known for her direct, no-BS style and her belief in testing, not guessing. Complex science becomes practical, actionable strategy—designed to fit real lives with demanding careers, families, and training schedules. Through 1:1 VIP coaching, online programs, functional lab testing, and education, Mary has helped hundreds of overwhelmed women shift from “there’s no time for me” to feeling strong, clear-headed, and consistent—while balancing it all. Her mission is simple: help women train hard, think clearly, age powerfully, and build health that supports both ambition and motherhood. Be Gutsy as a Mother.
