Why is it so hard to lose weight? What is metabolic adaptation? (Part 1/2)
References:
- Rosenbaum, M., Leibel, R. Adaptive thermogenesis in humans. Int J Obes 34 (Suppl 1), S47–S55 (2010). https://doi.org/10.1038/ijo.2010.184
- Bevilacqua, L., Ramsey, J. J., Hagopian, K., Weindruch, R., & Harper, M. E. (2004). Effects of short-and medium-term calorie restriction on muscle mitochondrial proton leak and reactive oxygen species production. American Journal of Physiology-Endocrinology and Metabolism, 286(5), E852-E861.
- Peos, J. J., Norton, L. E., Helms, E. R., Galpin, A. J., & Fournier, P. (2019). Intermittent dieting: theoretical considerations for the athlete. Sports, 7(1), 22.
- Trexler, E. T., Smith-Ryan, A. E., & Norton, L. E. (2014). Metabolic adaptation to weight loss: implications for the athlete. Journal of the International Society of Sports Nutrition, 11, 1-7.
- Ryan, D. H., & Yockey, S. R. (2017). Weight loss and improvement in comorbidity: differences at 5%, 10%, 15%, and over. Current obesity reports, 6, 187-194.
- O'Rourke, R. W. (2014). Metabolic thrift and the genetic basis of human obesity. Annals of surgery, 259(4), 642-648.
- Cowley, M. A., Pronchuk, N., Fan, W., Dinulescu, D. M., Colmers, W. F., & Cone, R. D. (1999). Integration of NPY, AGRP, and melanocortin signals in the hypothalamic paraventricular nucleus: evidence of a cellular basis for the adipostat. Neuron, 24(1), 155-163.
- Schwartz, M. W., Seeley, R. J., Zeltser, L. M., Drewnowski, A., Ravussin, E., Redman, L. M., & Leibel, R. L. (2017). Obesity pathogenesis: an endocrine society scientific statement. Endocrine reviews, 38(4), 267-296.
- Kennedy, G. C. (1953). The role of depot fat in the hypothalamic control of food intake in the rat. Proceedings of the Royal Society of London. Series B-Biological Sciences, 140(901), 578-592.
- Konturek, S. J., Konturek, P. C., Pawlik, T., & Brzozowski, T. (2004). Brain-gut axis and its role in the control of food intake. Journal of physiology and pharmacology, 55(2), 137-154.
- Wadden, T.A., Bantle, J.P., Blackburn, G.L., Bolin, P., Brancati, F.L., Bray, G.A. and Grp, L.A.R., 2014. Eight-year weight losses with an intensive lifestyle intervention: The look AHEAD study. Obesity, 22 (1), 5–13.
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Understanding Wegovy® Side Effects: What to Expect and How to Navigate Your Journey
Wegovy® (semaglutide) offers a promising new path for many who haven’t seen the changes they want. But like all prescription medications, Wegovy® can come with side effects — and it’s completely normal to feel a bit nervous. At rfynd Weight Loss, we believe in supporting you through your journey with care, empathy, and accurate information. Below, we’ve summarised the known side effects from the New Zealand Medsafe Data Sheet on Wegovy® to help you understand what to expect and when to seek support.
💬 The Most Common Side Effects: Gut Reactions
Gastrointestinal issues are the most frequently reported side effects of Wegovy, especially during the first few weeks when your dose is being gradually increased.
- Nausea – experienced by about 44% of people. Typically lasts on average for 8 days.
- Diarrhoea – reported by around 30% lasting 3 days on on average
- Vomiting – seen in roughly 25% usually on 2 days in duration.
- Constipation – 24% of patients experienced this with symptoms that can last a few weeks.
These symptoms are usually only mild to moderate and most people find they ease with time.
🧡 Other Digestive Symptoms to Know About
Some people also experience:
- Bloating
- Reflux or indigestion
- Stomach pain
- Gas or belching
- Hiccups
If you already have moderate kidney problems, these symptoms might be stronger — so it’s important to discuss this with your rfynd Weight Loss doctor.
💊 Less Common but Important Reactions
- Gallstones (Cholelithiasis) – Found in 1.6% of patients, with 0.6% developing gallbladder inflammation (cholecystitis). Please note, gallstone are very common even in those not on Wegovy®. Furthermore, significant weight loss by any means can lead to forming gallstones. It’s important to seek medical care if you experience severe abdominal pain.
- Hair loss – Reported in 2.5% of people. This is usually mild and happens more with greater weight loss (20%+), and often resolves on its own.
- Increased heart rate – A mild average increase of 3 beats per minute was seen. Around 26% of people had a temporary rise of 20+ bpm.
- Skin sensations – Tingling or sensitive skin reported by 2.1%. Typically mild and settles with time.
- Pancreatitis – Rare (0.2% incidence). It’s important to seek medical care if you experience severe abdominal pain.
- Kidney stones (Urolithiasis) – Occurred in about 1.2% of patients.
🔍 What About People with Type 2 Diabetes?
For those with diabetes:
- Low blood sugar (Hypoglycaemia) – Especially if taking sulfonylureas. It was seen in 6.2% of patients using Wegovy.
- Eye health (Diabetic retinopathy) – Observed in 4% of patients. Discuss with your clinician if you have existing eye disease.
👧🏽 And for Teens?
Wegovy® was studied in adolescents (12–17 years) for 68 weeks. Side effects were similar to adults, but gallstones occurred in 3.8%. Let your doctor know if you experience severe abdominal pain. There is no long-term data yet on use beyond 68 weeks in this age group.
🙋♀️ What Does This All Mean for You?
Most side effects are manageable and temporary. The rfynd clinical team is here to guide you with a judgment-free, professional approach. We offer tailored plans that include monitoring, support, and education — because sustainable weight loss should never feel isolating or overwhelming.
👉🏽 What’s Next?
If you’re considering Wegovy® or already taking it, you might find our companion blogs helpful:
📖 “Strategies to Manage Side Effects of Wegovy®” – practical tips, food strategies, and when to check in with your rfynd Weight Loss clinician.
Which Is the Safest Weight Loss Surgery?
Which is the Safest Weight Loss Surgery?
Exploring the Laparoscopic Gastric Sleeve, Roux-en-Y Gastric Bypass, and One-Anastomosis Gastric Bypass at rfynd Weight Loss
If you’re considering bariatric surgery, safety is likely one of your top concerns—and rightly so. At rfynd Weight Loss, we’re often asked:
“Which weight loss surgery is the safest?”
The good news is that all three of the surgical procedures we offer—Laparoscopic Gastric Sleeve, Roux-en-Y Gastric Bypass (RNYGB), and One-Anastomosis Gastric Bypass (OAGB)—are safe, well-established options when performed by an experienced surgical team with the right pre- and post-operative support.
That said, “safest” doesn’t always mean the same thing for everyone. The safest option for you will depend on your medical history, lifestyle, and goals.
Here’s how the three procedures compare.
1. Laparoscopic Gastric Sleeve (Sleeve Gastrectomy)
Often considered the safest first-line surgical option
What it involves:
About 80% of the stomach is removed, leaving a narrow “sleeve” that limits food intake and reduces hunger hormones.
Safety profile:
- No rerouting of the intestines = fewer anatomical changes
- Shorter surgery and hospital stay
- Lower risk of nutrient malabsorption compared to bypass procedures
Risks to consider:
- Can worsen or cause reflux in some people
- Irreversible (as part of the stomach is permanently removed)
Who it may be safest for:
People looking for a simpler procedure with a solid safety profile and effective long-term results, especially if they don’t have severe reflux or diabetes.
2. Roux-en-Y Gastric Bypass (RNYGB)
Tried-and-tested, especially for diabetes or reflux
What it involves:
A small stomach pouch is created and connected to the small intestine, bypassing most of the stomach and the first section of the intestine.
Safety profile:
- Decades of clinical use with well-documented outcomes
- Often improves or resolves type 2 diabetes quickly
- Can help with severe reflux or heartburn
- May provide more weight loss than sleeve in some cases
Risks to consider:
- Longer surgical time and slightly higher risk of complications
- Requires lifelong vitamin and mineral supplementation
- Small risk of internal hernia or marginal ulcer
Who it may be safest for:
People with reflux, diabetes, or who need significant weight loss and have no issue with a more complex procedure.
3. One-Anastomosis Gastric Bypass (OAGB or Mini Bypass)
A newer, simplified alternative to RNYGB with growing popularity
What it involves:
Similar to RNYGB, but with just one connection (anastomosis) between the stomach pouch and the intestine.
Safety profile:
- Shorter operation time than RNYGB
- Effective weight loss and diabetes resolution
- Slightly fewer surgical steps than RNYGB
Risks to consider:
- Can cause bile reflux in some people
- Nutrient deficiencies are still a consideration
- Long-term data is growing but not as extensive as RNYGB
Who it may be safest for:
People who want the effectiveness of a bypass with a simpler surgical approach—provided they are carefully screened for reflux risk.
So... Which Is the Safest?
In general terms:
- Gastric Sleeve is safest in terms of simplicity and fewer long-term nutritional concerns.
- RNYGB is safest for those with reflux or diabetes who need metabolic benefits.
- OAGB offers a middle ground—simpler than RNYGB, with strong results—but requires careful patient selection.
The safest surgery is the one tailored to you. That’s why at rfynd, every client goes through a full clinical review with a bariatric surgeon before making a decision.
How rfynd Prioritises Safety
Your safety is at the heart of everything we do. When you choose Rfynd, you can count on:
- Expert surgical teams in accredited private hospitals
- Pre-surgical assessments to determine the right procedure for your health
- Ongoing post-op support including medical, nutrition, and coaching follow-up
- A New Zealand-based team who understands your health system and lifestyle
Thinking About Weight Loss Surgery?
If you're wondering which weight loss surgery is safest for you, the best next step is to book a consultation with our expert bariatric surgeon, Dr Peter Carr-Boyd. During your consult, Dr Carr-Boyd will assess your individual health needs, explain your options, and guide you toward the procedure that offers the best balance of safety and long-term success.
👉 Book a consult with Dr Peter Carr-Boyd today
Wegovy Now Available in New Zealand | Start Medical Weight Loss with rfynd
Wegovy is now available in Aotearoa New Zealand— and at rfynd Weight Loss, we’re ready to support you with expert-led, compassionate medical weight loss care. Whether you're curious about semaglutide, comparing Wegovy and Ozempic, or wondering how to get started, here’s everything you need to know.
Wegovy vs Ozempic: What’s the Difference?
Both Wegovy and Ozempic contain the same active ingredient: semaglutide.
They’re both GLP-1 receptor agonists, which means they help regulate appetite and blood sugar — but they’re approved for different purposes:
- Ozempic is approved by Medsafe in NZ for the treatment of type 2 diabetes.
- Wegovy is also approved by Medsafe — but specifically for weight loss and obesity.
Although some people have used Ozempic “off-label” for weight loss, Wegovy is the correct formulation, dosage, and indication for treating obesity. That’s why Wegovy’s arrival in Aotearoa is such a big deal.
Wegovy has officially launched in NZ and is now available through rfynd Weight Loss. You can start today by booking a consultation with Dr Nicole Wilde.
Our Expert Team at rfynd
Whether you’re keen to try Saxenda, exploring Ozempic, waiting for Wegovy, or just want safe, effective support for weight loss, rfynd is here to help — with the right people by your side.
👩⚕️ Dr Nicole Wilde – Specialist Obesity Doctor
Dr Nicole Wilde is an Obesity Medicine Specialist and leading expert in medical weight management. Dr Nicole prescribes Wegovy and other weight management medications safely and appropriately, as part of a comprehensive treatment plan. She understands obesity is a complex, chronic condition — not a lack of willpower — and tailors medical care to your unique needs.
🥗 Kylie Russell – Specialist Dietitian
Medication works best when paired with nutrition and lifestyle support, and that’s where Kylie Russell comes in. With her expertise in gut health, weight loss, and sustainable eating, Kylie helps clients build confidence with food and manage any side effects from medications like Wegovy or Ozempic.
💬 Our Health Coaches
Making lasting change takes more than medication — and that’s where our health coaches come in. Our coaches provide practical tools, mindset support, and weekly accountability to help you stay on track. They work alongside our doctor and dietitian to guide you through every step of your journey, making healthy habits feel achievable and sustainable.
Together, the rfynd team provide evidence-based, whole-person care — because we know real success takes more than a script.
The rfynd Weight Loss Difference
We’re not a one-size-fits-all clinic. At rfynd, we offer:
- Online consults with our NZ-based team of specialists
- Ongoing support from our health coaches, nurse, dietitian and doctor
- Access to tools, apps, and personalised plans
- A supportive, stigma-free environment
We’re here to help you take control of your health.
Want to get started?
👉 Your next step is booking a consult with Dr Nicole Wilde, our specialist obesity doctor. Appointments are available online across New Zealand.
👉 Follow rfynd Weight Loss on Instagram or Facebook for updates on Wegovy, Ozempic, and other medical weight loss options in NZ.
📧 Prefer email? Contact us at support@rfynd.co.nz and we’ll be happy to help.
Your journey doesn’t have to wait — and we’re here to walk it with you.
Why Am I Not Seeing Any Testimonials Or Reviews Here?
The rfynd Programs are overseen by a team including medical specialists, dietitians, health psychologists and nurses.
Under New Zealand regulations, these professionals are unable to use reviews or testimonials to advertise their services.
If you have any questions about our services and how they might benefit you, we'd love to talk.
