Digestion & Nutrient Absorption
Digestive health & nutrient-absorption blood tests
Compare celiac antibody and targeted nutrient packages for digestive concerns, prior surgery or a known condition. Each option has a specific purpose and a complete test list.
Start here
Which package fits your question?
Considering a gluten-free diet
Review the $120 celiac antibody package before changing your diet. It lists tTG IgA and IgG antibodies with general bloodwork. Ask your clinician which tests and timing are appropriate for your history.
Nutrition after gastrointestinal surgery
The gastric sleeve, bypass and ileal surgery packages address different questions. Check the actual B12, iron, copper or zinc tests and compare them with your care team’s follow-up plan.
A known digestive condition or medicine
Packages related to IBD, reflux medication and loose stools are focused combinations. They complement a clinical assessment; they do not measure every cause of malabsorption.
Explore the test details
Digestion & Nutrient Absorption
Compare prices and expand each test list. Package names can overlap in purpose and biomarkers; choosing more than one may repeat tests.
Copper & Zinc After Gastric Bypass
If you’ve had gastric bypass, zinc and copper deserve a place in your supplement review. Too much zinc can make copper harder to absorb, and low copper can affect blood counts and nerves. Take the results and your multivitamin label to your bariatric team.
View all 54 biomarkers
- Glucose (Blood)
- Creatinine
- BUN/Creatinine Ratio
- Estimated Glomerular Filtration Rate
- Calcium
- Blood Urea Nitrogen
- Carbon Dioxide
- Chloride
- Potassium
- Sodium
- Albumin/Globulin Ratio
- Total Bilirubin
- Globulin (Calculated)
- Alkaline Phosphatase (ALP)
- Albumin
- Aspartate Aminotransferase (AST)
- Alanine Aminotransferase (ALT)
- Protein, Total
- Copper
- Ceruloplasmin
- Zinc, RBC
- Red Cell Distribution Width (RDW)
- Neutrophils (%)
- Monocytes (%)
- Lymphocytes (%)
- Eosinophils (%)
- Basophils (%)
- Platelet Count
- Mean Corpuscular Hemoglobin Concentration (MCHC)
- Mean Corpuscular Hemoglobin (MCH)
- Mean Corpuscular Volume
- Hematocrit
- Hemoglobin (HGB)
- Band Neutrophils
- Blasts
- Metamyelocytes
- Myelocytes
- Nucleated RBC
- Promyelocytes
- Band Neutrophils (%)
- Basophils
- Blasts (%)
- Eosinophils
- Lymphocytes
- Metamyelocytes (%)
- Monocytes
- Myelocytes (%)
- Neutrophils
- Nucleated RBC (%)
- Promyelocytes (%)
- Reactive Lymphocytes
- Mean Platelet Volume (MPV)
- White Blood Cell Count (WBC)
- Red Blood Cell Count (RBC)
Quest blood collection included.
Why Am I Tired After Gastric Sleeve Surgery?
Smaller portions and changes in digestion can make it harder to meet nutrient needs after sleeve surgery. If your energy has dipped, compare the nutrients used to make red blood cells with your bariatric team’s targets. This focused panel fits alongside your scheduled postoperative monitoring.
View all 57 biomarkers
- Glucose (Blood)
- Creatinine
- BUN/Creatinine Ratio
- Estimated Glomerular Filtration Rate
- Calcium
- Blood Urea Nitrogen
- Carbon Dioxide
- Chloride
- Potassium
- Sodium
- Albumin/Globulin Ratio
- Total Bilirubin
- Globulin (Calculated)
- Alkaline Phosphatase (ALP)
- Albumin
- Aspartate Aminotransferase (AST)
- Alanine Aminotransferase (ALT)
- Protein, Total
- Iron, Total
- Ferritin
- Total Iron Binding Capacity (TIBC)
- Iron % Saturation
- Folate
- Vitamin B12 (Cobalamin)
- Red Cell Distribution Width (RDW)
- Neutrophils (%)
- Monocytes (%)
- Lymphocytes (%)
- Eosinophils (%)
- Basophils (%)
- Platelet Count
- Mean Corpuscular Hemoglobin Concentration (MCHC)
- Mean Corpuscular Hemoglobin (MCH)
- Mean Corpuscular Volume
- Hematocrit
- Hemoglobin (HGB)
- Band Neutrophils
- Blasts
- Metamyelocytes
- Myelocytes
- Nucleated RBC
- Promyelocytes
- Band Neutrophils (%)
- Basophils
- Blasts (%)
- Eosinophils
- Lymphocytes
- Metamyelocytes (%)
- Monocytes
- Myelocytes (%)
- Neutrophils
- Nucleated RBC (%)
- Promyelocytes (%)
- Reactive Lymphocytes
- Mean Platelet Volume (MPV)
- White Blood Cell Count (WBC)
- Red Blood Cell Count (RBC)
Quest blood collection included.
B12 & Magnesium on Long-Term Reflux Medication
If you take a proton pump inhibitor long term and have a previous deficiency, persistent cramps or another risk factor, ask whether these checks fit your care. They help you decide whether B12 or magnesium deserves attention before adding another supplement.
View all 54 biomarkers
- Glucose (Blood)
- Creatinine
- BUN/Creatinine Ratio
- Estimated Glomerular Filtration Rate
- Calcium
- Blood Urea Nitrogen
- Carbon Dioxide
- Chloride
- Potassium
- Sodium
- Albumin/Globulin Ratio
- Total Bilirubin
- Globulin (Calculated)
- Alkaline Phosphatase (ALP)
- Albumin
- Aspartate Aminotransferase (AST)
- Alanine Aminotransferase (ALT)
- Protein, Total
- Magnesium (RBC)
- Folate
- Vitamin B12 (Cobalamin)
- Red Cell Distribution Width (RDW)
- Neutrophils (%)
- Monocytes (%)
- Lymphocytes (%)
- Eosinophils (%)
- Basophils (%)
- Platelet Count
- Mean Corpuscular Hemoglobin Concentration (MCHC)
- Mean Corpuscular Hemoglobin (MCH)
- Mean Corpuscular Volume
- Hematocrit
- Hemoglobin (HGB)
- Band Neutrophils
- Blasts
- Metamyelocytes
- Myelocytes
- Nucleated RBC
- Promyelocytes
- Band Neutrophils (%)
- Basophils
- Blasts (%)
- Eosinophils
- Lymphocytes
- Metamyelocytes (%)
- Monocytes
- Myelocytes (%)
- Neutrophils
- Nucleated RBC (%)
- Promyelocytes (%)
- Reactive Lymphocytes
- Mean Platelet Volume (MPV)
- White Blood Cell Count (WBC)
- Red Blood Cell Count (RBC)
Quest blood collection included.
Losing Fluid With Frequent Loose Stools?
Repeated loose stools can mean losing fluid and salts faster than you replace them. Review sodium, potassium, bicarbonate, kidney function and magnesium with your clinician while they investigate the diarrhea. The results can guide a more individual fluid and electrolyte plan.
View all 52 biomarkers
- Glucose (Blood)
- Creatinine
- BUN/Creatinine Ratio
- Estimated Glomerular Filtration Rate
- Calcium
- Blood Urea Nitrogen
- Carbon Dioxide
- Chloride
- Potassium
- Sodium
- Albumin/Globulin Ratio
- Total Bilirubin
- Globulin (Calculated)
- Alkaline Phosphatase (ALP)
- Albumin
- Aspartate Aminotransferase (AST)
- Alanine Aminotransferase (ALT)
- Protein, Total
- Magnesium (RBC)
- Red Cell Distribution Width (RDW)
- Neutrophils (%)
- Monocytes (%)
- Lymphocytes (%)
- Eosinophils (%)
- Basophils (%)
- Platelet Count
- Mean Corpuscular Hemoglobin Concentration (MCHC)
- Mean Corpuscular Hemoglobin (MCH)
- Mean Corpuscular Volume
- Hematocrit
- Hemoglobin (HGB)
- Band Neutrophils
- Blasts
- Metamyelocytes
- Myelocytes
- Nucleated RBC
- Promyelocytes
- Band Neutrophils (%)
- Basophils
- Blasts (%)
- Eosinophils
- Lymphocytes
- Metamyelocytes (%)
- Monocytes
- Myelocytes (%)
- Neutrophils
- Nucleated RBC (%)
- Promyelocytes (%)
- Reactive Lymphocytes
- Mean Platelet Volume (MPV)
- White Blood Cell Count (WBC)
- Red Blood Cell Count (RBC)
Quest blood collection included.
B12 After Ileal Surgery
The last part of the small intestine plays a key role in absorbing B12. After surgery there, a B12 result can be hard to read on its own. MMA adds context, and kidney function helps your clinician interpret it when deciding whether your current replacement plan is working.
View all 54 biomarkers
- Glucose (Blood)
- Creatinine
- BUN/Creatinine Ratio
- Estimated Glomerular Filtration Rate
- Calcium
- Blood Urea Nitrogen
- Carbon Dioxide
- Chloride
- Potassium
- Sodium
- Albumin/Globulin Ratio
- Total Bilirubin
- Globulin (Calculated)
- Alkaline Phosphatase (ALP)
- Albumin
- Aspartate Aminotransferase (AST)
- Alanine Aminotransferase (ALT)
- Protein, Total
- Folate
- Vitamin B12 (Cobalamin)
- Methylmalonic Acid
- Red Cell Distribution Width (RDW)
- Neutrophils (%)
- Monocytes (%)
- Lymphocytes (%)
- Eosinophils (%)
- Basophils (%)
- Platelet Count
- Mean Corpuscular Hemoglobin Concentration (MCHC)
- Mean Corpuscular Hemoglobin (MCH)
- Mean Corpuscular Volume
- Hematocrit
- Hemoglobin (HGB)
- Band Neutrophils
- Blasts
- Metamyelocytes
- Myelocytes
- Nucleated RBC
- Promyelocytes
- Band Neutrophils (%)
- Basophils
- Blasts (%)
- Eosinophils
- Lymphocytes
- Metamyelocytes (%)
- Monocytes
- Myelocytes (%)
- Neutrophils
- Nucleated RBC (%)
- Promyelocytes (%)
- Reactive Lymphocytes
- Mean Platelet Volume (MPV)
- White Blood Cell Count (WBC)
- Red Blood Cell Count (RBC)
Quest blood collection included.
Why Am I So Tired With IBD?
Crohn’s or colitis can leave you exhausted even when you’ve been trying to eat enough iron. Your IBD team can use your blood count, iron availability and inflammation marker together to assess anemia and decide whether nutrition support or medical treatment needs adjusting.
View all 56 biomarkers
- hsCRP
- Glucose (Blood)
- Creatinine
- BUN/Creatinine Ratio
- Estimated Glomerular Filtration Rate
- Calcium
- Blood Urea Nitrogen
- Carbon Dioxide
- Chloride
- Potassium
- Sodium
- Albumin/Globulin Ratio
- Total Bilirubin
- Globulin (Calculated)
- Alkaline Phosphatase (ALP)
- Albumin
- Aspartate Aminotransferase (AST)
- Alanine Aminotransferase (ALT)
- Protein, Total
- Iron, Total
- Ferritin
- Total Iron Binding Capacity (TIBC)
- Iron % Saturation
- Red Cell Distribution Width (RDW)
- Neutrophils (%)
- Monocytes (%)
- Lymphocytes (%)
- Eosinophils (%)
- Basophils (%)
- Platelet Count
- Mean Corpuscular Hemoglobin Concentration (MCHC)
- Mean Corpuscular Hemoglobin (MCH)
- Mean Corpuscular Volume
- Hematocrit
- Hemoglobin (HGB)
- Band Neutrophils
- Blasts
- Metamyelocytes
- Myelocytes
- Nucleated RBC
- Promyelocytes
- Band Neutrophils (%)
- Basophils
- Blasts (%)
- Eosinophils
- Lymphocytes
- Metamyelocytes (%)
- Monocytes
- Myelocytes (%)
- Neutrophils
- Nucleated RBC (%)
- Promyelocytes (%)
- Reactive Lymphocytes
- Mean Platelet Volume (MPV)
- White Blood Cell Count (WBC)
- Red Blood Cell Count (RBC)
Quest blood collection included.
My Celiac Follow-Up After Going Gluten-Free
For diagnosed celiac disease with a previously informative IgA antibody result, this follow-up pairs the antibody trend with iron stores and vitamin D. It gives you useful questions for your next visit about accidental gluten exposure, nutrient replacement and how recovery is going.
View all 58 biomarkers
- Glucose (Blood)
- Creatinine
- BUN/Creatinine Ratio
- Estimated Glomerular Filtration Rate
- Calcium
- Blood Urea Nitrogen
- Carbon Dioxide
- Chloride
- Potassium
- Sodium
- Albumin/Globulin Ratio
- Total Bilirubin
- Globulin (Calculated)
- Alkaline Phosphatase (ALP)
- Albumin
- Aspartate Aminotransferase (AST)
- Alanine Aminotransferase (ALT)
- Protein, Total
- Vitamin D, 25-OH, Total
- Iron, Total
- Ferritin
- Total Iron Binding Capacity (TIBC)
- Iron % Saturation
- Red Cell Distribution Width (RDW)
- Neutrophils (%)
- Monocytes (%)
- Lymphocytes (%)
- Eosinophils (%)
- Basophils (%)
- Platelet Count
- Mean Corpuscular Hemoglobin Concentration (MCHC)
- Mean Corpuscular Hemoglobin (MCH)
- Mean Corpuscular Volume
- Hematocrit
- Hemoglobin (HGB)
- Band Neutrophils
- Blasts
- Metamyelocytes
- Myelocytes
- Nucleated RBC
- Promyelocytes
- Band Neutrophils (%)
- Basophils
- Blasts (%)
- Eosinophils
- Lymphocytes
- Metamyelocytes (%)
- Monocytes
- Myelocytes (%)
- Neutrophils
- Nucleated RBC (%)
- Promyelocytes (%)
- Reactive Lymphocytes
- Mean Platelet Volume (MPV)
- White Blood Cell Count (WBC)
- Red Blood Cell Count (RBC)
- Tissue Transglutaminase (tTG) Antibody (IgA)
- Tissue Transglutaminase (tTG) Antibody (IgG)
Quest blood collection included.
Why Does My Iron Keep Dropping?
You’ve worked on your iron intake, yet your stores keep falling. Celiac disease is one possible reason iron can be hard to absorb, even with few digestive symptoms. This combination rechecks iron status and screens for celiac while you’re eating gluten. Your clinician can also look for sources of blood loss.
View all 57 biomarkers
- Glucose (Blood)
- Creatinine
- BUN/Creatinine Ratio
- Estimated Glomerular Filtration Rate
- Calcium
- Blood Urea Nitrogen
- Carbon Dioxide
- Chloride
- Potassium
- Sodium
- Albumin/Globulin Ratio
- Total Bilirubin
- Globulin (Calculated)
- Alkaline Phosphatase (ALP)
- Albumin
- Aspartate Aminotransferase (AST)
- Alanine Aminotransferase (ALT)
- Protein, Total
- Iron, Total
- Ferritin
- Total Iron Binding Capacity (TIBC)
- Iron % Saturation
- Red Cell Distribution Width (RDW)
- Neutrophils (%)
- Monocytes (%)
- Lymphocytes (%)
- Eosinophils (%)
- Basophils (%)
- Platelet Count
- Mean Corpuscular Hemoglobin Concentration (MCHC)
- Mean Corpuscular Hemoglobin (MCH)
- Mean Corpuscular Volume
- Hematocrit
- Hemoglobin (HGB)
- Band Neutrophils
- Blasts
- Metamyelocytes
- Myelocytes
- Nucleated RBC
- Promyelocytes
- Band Neutrophils (%)
- Basophils
- Blasts (%)
- Eosinophils
- Lymphocytes
- Metamyelocytes (%)
- Monocytes
- Myelocytes (%)
- Neutrophils
- Nucleated RBC (%)
- Promyelocytes (%)
- Reactive Lymphocytes
- Mean Platelet Volume (MPV)
- White Blood Cell Count (WBC)
- Red Blood Cell Count (RBC)
- Tissue Transglutaminase (tTG) Antibody (IgA)
- Tissue Transglutaminase (tTG) Antibody (IgG)
Quest blood collection included.
Celiac Testing When IgA Is Low
Already told you have IgA deficiency? The usual IgA celiac screen can miss important information. This bloodwork uses IgG antibodies to explore whether gluten-related intestinal injury deserves further evaluation. Plan it with your clinician while you’re eating gluten.
View all 54 biomarkers
- Glucose (Blood)
- Creatinine
- BUN/Creatinine Ratio
- Estimated Glomerular Filtration Rate
- Calcium
- Blood Urea Nitrogen
- Carbon Dioxide
- Chloride
- Potassium
- Sodium
- Albumin/Globulin Ratio
- Total Bilirubin
- Globulin (Calculated)
- Alkaline Phosphatase (ALP)
- Albumin
- Aspartate Aminotransferase (AST)
- Alanine Aminotransferase (ALT)
- Protein, Total
- Red Cell Distribution Width (RDW)
- Neutrophils (%)
- Monocytes (%)
- Lymphocytes (%)
- Eosinophils (%)
- Basophils (%)
- Platelet Count
- Mean Corpuscular Hemoglobin Concentration (MCHC)
- Mean Corpuscular Hemoglobin (MCH)
- Mean Corpuscular Volume
- Hematocrit
- Hemoglobin (HGB)
- Band Neutrophils
- Blasts
- Metamyelocytes
- Myelocytes
- Nucleated RBC
- Promyelocytes
- Band Neutrophils (%)
- Basophils
- Blasts (%)
- Eosinophils
- Lymphocytes
- Metamyelocytes (%)
- Monocytes
- Myelocytes (%)
- Neutrophils
- Nucleated RBC (%)
- Promyelocytes (%)
- Reactive Lymphocytes
- Mean Platelet Volume (MPV)
- White Blood Cell Count (WBC)
- Red Blood Cell Count (RBC)
- Gliadin (Deamidated) Antibody (IgG)
- Tissue Transglutaminase (tTG) Antibody (IgA)
- Tissue Transglutaminase (tTG) Antibody (IgG)
Quest blood collection included.
Always Bloated? Check for Celiac Before Going Gluten-Free
If bloating or loose stools have you thinking about giving up gluten, timing matters. Celiac antibodies are most informative while you’re still regularly eating gluten. This package lists tTG IgA and IgG antibodies alongside a CMP and CBC. Discuss the right tests and timing with your clinician, especially if you already avoid gluten.
Package details & cost →View all 53 biomarkers
- Glucose (Blood)
- Creatinine
- BUN/Creatinine Ratio
- Estimated Glomerular Filtration Rate
- Calcium
- Blood Urea Nitrogen
- Carbon Dioxide
- Chloride
- Potassium
- Sodium
- Albumin/Globulin Ratio
- Total Bilirubin
- Globulin (Calculated)
- Alkaline Phosphatase (ALP)
- Albumin
- Aspartate Aminotransferase (AST)
- Alanine Aminotransferase (ALT)
- Protein, Total
- Red Cell Distribution Width (RDW)
- Neutrophils (%)
- Monocytes (%)
- Lymphocytes (%)
- Eosinophils (%)
- Basophils (%)
- Platelet Count
- Mean Corpuscular Hemoglobin Concentration (MCHC)
- Mean Corpuscular Hemoglobin (MCH)
- Mean Corpuscular Volume
- Hematocrit
- Hemoglobin (HGB)
- Band Neutrophils
- Blasts
- Metamyelocytes
- Myelocytes
- Nucleated RBC
- Promyelocytes
- Band Neutrophils (%)
- Basophils
- Blasts (%)
- Eosinophils
- Lymphocytes
- Metamyelocytes (%)
- Monocytes
- Myelocytes (%)
- Neutrophils
- Nucleated RBC (%)
- Promyelocytes (%)
- Reactive Lymphocytes
- Mean Platelet Volume (MPV)
- White Blood Cell Count (WBC)
- Red Blood Cell Count (RBC)
- Tissue Transglutaminase (tTG) Antibody (IgA)
- Tissue Transglutaminase (tTG) Antibody (IgG)
Quest blood collection included.
Before you choose
Useful answers.
Is this a food intolerance or microbiome test?
These are blood-test packages. The celiac options measure specified antibodies. They are not broad food-intolerance panels, stool microbiome tests or tests for every food reaction.
Can I test for celiac disease after going gluten-free?
A gluten-free diet can affect antibody results. Work with your clinician on timing and the appropriate tests before changing gluten intake again.
Do these replace my post-surgery monitoring plan?
Use your surgery team’s recommended tests and schedule. The packages differ, and additional markers may be appropriate for your procedure and history.
Cost and collection
Packages in this category cost $95–$155. Quest blood collection is included in the listed price. Review available Quest locations for your address during ordering.
Preparation and results
Follow your selected package’s instructions for fasting and other preparation. Your provider reviews your results and shares next steps. Testing is cash-pay; every lab package in this store is HSA/FSA eligible.
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Information from New Approach Health. Prices and included markers checked November 7, 2026.
Further reading: NIDDK: diagnosis of celiac diseaseNIDDK: celiac disease tests