After weight-loss surgery · Plymouth
Blood test monitoring after weight-loss surgery.
Gastric bypass, sleeve and band surgery change how you absorb nutrients for life. We offer the monitoring the national guidelines recommend, with no GP referral needed.
Why it matters
Lifelong checks, not an optional extra.
After surgery, low levels of Iron, B12, Vitamin D, Calcium and other nutrients can build up slowly, without symptoms, until they cause harm.
The NHS usually discharges patients from bariatric follow-up within 1 to 2 years. Many people are then left without the monitoring their surgery needs. We fill that gap at our Plymouth clinic.
Good to know
- Panels set by surgery type and time since surgery
- Blood draw included in the price
- Bring your supplement list and we will check it against your results
- A follow-up appointment if a result needs discussing
- Prices are on our price list
Common shortfalls
What we look for.
Less stomach acid and a bypassed gut make Iron harder to absorb.
A smaller stomach makes less of it. Low B12 can cause nerve damage and anaemia.
Calcium is mainly absorbed in the part of the gut that is bypassed.
Lower food intake can mean lower levels.
Often low after bypass or sleeve surgery.
Only a blood test shows whether your supplements are working.
Gastric bypass and sleeve
Checks at 3, 6 and 12 months, then every year.
These operations carry the highest risk of low levels. The panel grows at each stage. Results usually take 2 to 3 working days.
| 3 months after surgery | |
|---|---|
| Blood count | Full Blood Count |
| Iron | Serum Iron, TIBC and Ferritin |
| Vitamins | Vitamin B12, Folate, Vitamin D and Thiamine (Vitamin B1) |
| Bone | Calcium |
| Blood sugar and cholesterol | HbA1c, Cholesterol, HDL, LDL and Triglycerides |
| Liver and kidney | Liver function and kidney function |
| 6 months | Adds Parathyroid Hormone (PTH), Magnesium, Copper, Selenium, Zinc and Albumin. |
| 12 months and every year | Adds Vitamin A, Vitamin E, CRP, Phosphate and ALP. |
Gastric band
Checks at 6 months, then every year.
A band does not bypass any of the gut, so the risk is lower. Low levels can still develop from eating less. Most results the next working day.
| 6 months after surgery | |
|---|---|
| Blood count | Full Blood Count |
| Iron | Serum Iron and Transferrin Saturation |
| Vitamins | Vitamin B12, Folate and Vitamin D |
| Bone | Calcium |
| Liver and kidney | Liver function and kidney function |
| Every year | Adds Parathyroid Hormone (PTH), Magnesium, Zinc, Albumin, CRP and a cholesterol panel. |
Prices for every panel are on our price list.
How it works
Four simple steps.
Bring any previous results and we will do the rest.
Book
Tell us your surgery type and when you had it. We confirm the right panel before you arrive.
Fill in your new patient form
Once you have booked, we send you a form about your health, medicines and supplements.
Blood sample
Taken at our Plymouth clinic. It takes about 15 to 20 minutes.
Results
Emailed with a clinician summary. If a result is low, we advise on next steps.
Right here in Plymouth
Local care, close to home.
Your blood test is at Tor Clinical Rooms, 3 Darklake View, Plymouth PL6 7TL. Free parking on site, and easy to reach from the A38.
Questions people ask
About monitoring after weight-loss surgery.
Monitoring
My GP says my bloods are fine. Do I still need this?
GP blood tests often cover only some of the markers in the national guidelines. They may not include PTH, Zinc, Copper, Selenium or a full Iron panel. Unless your GP ordered a post-surgery panel, key markers may not have been checked.
How long do I need blood tests for?
After a bypass or sleeve, the guidelines recommend a yearly check for life. Even people who feel well, eat well and take supplements can develop low levels.
I was discharged years ago. Is it too late?
No. We usually start with the full annual panel to see where your levels are, then advise on a schedule. Low Iron, B12 and Vitamin D are easy to treat once found.
Can you look at my previous results?
Yes. Bring them along and we will compare them with your new results.
Your results
What if a result is low?
We contact you with your results and advise on next steps. That might mean changing your supplement dose or type, a repeat test in 3 months, or a letter for your GP.
Do I need to fast?
For panels that include cholesterol, please do not eat for 10 hours before. Water is fine. If fasting is hard because of your diet after surgery, tell us when you book and we will advise.
Can I add other tests?
Yes. Many markers overlap with our other profiles, so we can add tests such as a full Thyroid check without doubling up. Just ask when you book.
What our patients say

Book your post-surgery blood test
No GP referral needed. Most results the next working day.








