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Castellano Health Institute
(714) 530-2183
Medical Weight Loss · Orange County

Medical weight loss, the labs-led way. Built around your metabolism, not a script.

Most men and women walking into a weight-loss clinic have an unread thyroid, insulin, or hormone signal in their labs that nobody has actually looked at yet. Dr. Castellano runs the panel before deciding what — if anything — to prescribe. Sometimes the medication is the right tool. Sometimes the right tool is a thyroid prescription that nobody else thought to check for.

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Full panel up frontHonest read on what the numbers sayNo package memberships
What the visit fee covers

The 1-hour consultation, the full hormone and metabolic panel ordering and review, and the conversation about what to do next. If medication ends up being part of the plan, pricing for the specific protocol is quoted in the visit — it varies enough by class that an honest number requires the labs first.

No package commitments. No long-term contracts. If the protocol isn’t working for you, you stop any month.

Call (714) 530-2183
The Honest Read

Most weight-loss clinics start with the medication.

That model exists because it’s easy to scale. Same protocol, same drug, same dose, same monthly subscription — across hundreds of patients. It works some of the time, fails most of the time, and skips the question of whether a medication was even the right answer.

The honest medical version is older and slower: figure out what’s actually driving the weight first, then build the plan around that. Many weight-loss patients have an underlying hormone or metabolic signal in the labs that changes the conversation.

Man pinching his abdominal weight with both hands — the stubborn middle-section weight that doesn't move with the same diet that worked five years ago
Where men’s health actually starts

Eight of the top ten causes of death in American men trace back to one underlying condition: insulin resistance.

It’s the focus of how we approach metabolic care — and the reason the panel runs wider than the scale alone.

The Initial Panel

What gets checked before any prescription gets written.

The same panel that anchors TRT and anti-aging workups. If you have recent bloodwork from another provider, bring it. If not, the lab order goes out the same day you call.

  • Total + free testosterone
  • TSH + free T4
  • Fasting insulin + HbA1c
  • Lipid panel (LDL, HDL, triglycerides)
  • Comprehensive metabolic panel
  • Vitamin D + B12 + ferritin
  • Cortisol (where indicated)
  • Hs-CRP (inflammation marker)
Common Findings

The labs often change the plan.

Patterns that get missed when nobody runs the panel — and that quietly undermine every diet attempt.

  • Subclinical low thyroid (TSH borderline-high, free T4 unread)
  • Low testosterone in men past 40 (drives abdominal weight gain quietly)
  • Insulin resistance (fasting insulin elevated; A1c still inside range)
  • Vitamin D deficiency (common in adults working indoors)
  • Suppressed estrogen / progesterone in perimenopausal women
  • Side effects of an unrelated medication you've been on for years
When Medication Helps

Biology is the limiter.

Insulin resistance that food alone won’t fix. Satiety dysregulation from years of metabolic stress. Hormonal patterns that drive abdominal fat storage independent of caloric intake. These are the cases where medication earns its place — it changes a biological set point that willpower can’t reach.

For these patients, the plan typically pairs the medication with hormone correction (often TRT) and lifestyle scaffolding. The medication is the lever; the rest is what makes the lever land somewhere durable.

When It Doesn’t

Lifestyle is the limiter.

Five hours of sleep a night. Ultra-processed food in the kitchen. Three drinks most evenings. No daily movement. A weight-loss medication prescribed into that picture will produce a short window of progress followed by a regain. The medication can’t out-engineer the underlying inputs.

For these patients, Dr. Castellano will be straight: fix two of those four first, recheck in 12 weeks, and then have an honest conversation about whether medication is still the right next step. That’s the old-school doctor answer. It works.

How It Works

Four steps. Same shape as TRT, different lab focus.

  1. 01

    Sit-down visit

    1-hour, 1-on-1 with Dr. Castellano. Walk through the labs together. Honest read on what's driving the weight.

  2. 02

    Bloodwork

    Full hormone + metabolic panel. Lab order out from the visit. Bring outside results if you have them.

  3. 03

    Build the plan

    Hormone correction if indicated. Medication if the biology says it'll land. Lifestyle scaffolding either way.

  4. 04

    Recheck + adjust

    Lab recheck at 6 weeks, then quarterly. Dose tuning, plan adjustment, plateau-breaking — all based on the numbers and how you feel.

Dr. Castellano — Orange County medical weight loss physician since 1999
About the Doctor

Decades of reading metabolic patterns in the same Orange County market.

UC Irvine School of Medicine ('96). Board-certified in Family Medicine (ABFM). Advanced certifications in Anti-Aging and Regenerative Medicine (ABAARM, Anti-Aging Fellowship). Practicing in Orange County since 1999.

Weight loss done as honest medicine looks different from weight loss done as franchise pharmacology. Same chart, same doctor, same lab eye — visit after visit, quarter after quarter, year after year.

UC Irvine '96
School of Medicine
ABFM
Family Medicine
ABAARM
Anti-Aging board
Fellowship
Anti-Aging
Common Questions

The questions patients actually ask before they call.

Don’t see yours? Call the office and ask Dr. Castellano directly.

Do I need to be a certain weight to be a candidate?
No fixed cutoff. The decision is driven by labs, body composition, medical history, and what you're trying to accomplish — not by a number on the scale. Some patients walk in for weight loss and leave with a thyroid prescription. Others walk in and leave with a lifestyle plan that doesn't involve a medication at all.
What if my insurance covers a weight-loss medication — can you still see me?
Yes. Dr. Castellano runs the visit and the workup; the prescription itself goes to whatever pharmacy your insurance prefers. The medical evaluation isn't tied to where you fill the script.
Do you prescribe GLP-1-class medications?
The GLP-1 receptor-agonist class is one tool when labs and clinical picture support it. Whether it's the right fit for a specific patient is a case-by-case call made in the visit, after the bloodwork and history are on the table. Specifics get discussed in person, not on a marketing page.
How fast should I expect to see weight come off?
Realistic expectation: 1–2 lbs/week of fat loss when the plan is dialed in. Faster initial drops in the first 2–3 weeks are usually water and glycogen. Anyone promising 5+ lbs/week is selling water loss or worse — that's not how human metabolism works.
What happens if the labs come back normal but I still want to lose 30 lbs?
Then the conversation shifts to lifestyle scaffolding — sleep, training, nutrition, alcohol, daily movement. Sometimes the answer is unsexy: your hormones are fine, the math just needs to change. Dr. Castellano will be straight with you about it rather than handing over a prescription you don't need.
Do I need to come into the office monthly, or can follow-ups be telehealth?
Mix is typical. In-person for the initial visit and lab-recheck visits; telehealth fine for between-recheck adjustments. The cadence is matched to where you are in the protocol.
What if I plateau at month three?
Plateaus happen and they're rarely a failure of the plan — usually a signal that something needs adjusting (medication dose, training stimulus, sleep, sometimes a lab recheck). Dr. Castellano runs through the variables and adjusts what needs adjusting. Plateaus are a normal part of the protocol, not a reason to abandon it.
Can I do this alongside TRT?
Often yes — the two protocols share a lab panel and reinforce each other. Low testosterone contributes to abdominal weight gain in men, so for many patients the TRT plan is doing some of the weight-loss work invisibly in the background. The combined plan gets walked through in the visit.
Patient Voices

Real patients. Real reviews. Verified by Google.

Serving Orange County

Medical weight loss for the Orange County corridor.

The clinic sits on S Euclid St in Garden Grove — easy reach from Anaheim, Westminster, Santa Ana, and the wider OC corridor. Free on-site parking.

We see patients from Garden Grove, Anaheim, Westminster, Stanton, Santa Ana, Cypress, Buena Park, Orange, Fountain Valley, Huntington Beach, Costa Mesa, Tustin, Fullerton, Long Beach, Los Angeles, and across Orange County.

Ready when you are

Book the 1-hour consult.

Bring whatever bloodwork you have on file. If you don’t have any, the lab order goes out same day — the visit happens after the panel comes back so the conversation is grounded in real numbers, not guesswork.

Call (714) 530-2183Get directions
12460 S Euclid St, #101 · Garden Grove, CA 92840
Mon–Fri 9 AM – 5 PM

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