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Baseline Blood Tests and Important Considerations When Following The Program

Updated: May 13

At Weight Loss by Gina, we strongly believe in empowering our members with knowledge. This can help them take charge of their own health, as well as seek guidance from their team of health care providers. 

Many members come into The Program not only with weight to lose but also with health issues that may be a contributing factor to their weight gain. 

As you embark on this journey of weight loss and wellness, it is beneficial to have accurate information about the state of your health. Part of that would be partnering with your health care providers (HCP) and sharing The Program with them, including The Food Plan. Many people come into The Program taking medications that will need monitoring as they lose weight. Many find that they need adjustments to their medications as they progress through their journey of weight loss or may even be able to discontinue them. 

As a part of self-accountability and advocacy, when starting The Program, it is recommended to have a physical assessment completed by your health care provider, as well as baseline blood work to have insight into where you are starting from. It is then recommended to follow up on this blood work after 6 months (or as recommended by your health care provider depending on your health issues) to monitor any changes in your health status and blood work values. This is a great quantitative (or numerical) measure of your progress as well as a non-scale victory. 

We will be discussing some common baseline blood tests that can provide general information about your health, as well as those that can provide awareness of why your body may be feeling the need to store fat. 

*This post does not replace the guidance of your health care provider. It is not medical advice and is strictly for supplemental information. If you have any questions or concerns, please follow up with your health care provider.

What is a blood test and what does it show?

Your blood is composed of both liquid and solid components. The liquid part, called plasma, is made of water, salts and protein. Over half of your blood is plasma. The solid part of your blood contains red blood cells, white blood cells and platelets. 

Blood tests are used to measure or examine cells, chemicals, proteins or other substances in the blood. Blood testing, also known as blood work, is one of the most common types of lab tests. 

Blood tests are an important part of health monitoring and can help health care providers check for certain diseases and conditions, as well as keep track of your overall physical well-being. They also help to check the function of your organs, diagnose bleeding or clotting disorders, determine if your immune system is having trouble fighting infections, check for vitamin or mineral deficiencies and also show how well treatments are working. A blood test may even show whether a person may be at risk of developing certain conditions. 

People on medications may need a blood test to assess how well medications are working, or whether doses need to be adjusted. 

Examples of organ issues that can be visible in a blood test include your thyroid, liver, heart or kidneys. 

Your health care provider can also use blood tests to search for markers of diseases and health conditions, such as: 

  • Diabetes 

  • HIV 

  • Anemia 

  • Cancer 

  • Coronary heart disease 

  • Blood clotting issues 

  • A hypo/hyper thyroid 

  • Kidney and liver disease 

  • Infection and low immunity 

  • Vitamin/mineral deficiencies 

Getting tested at routine intervals allows you to see how your body changes over time and can empower you to make informed decisions about your health. This is why it would be a great benefit to monitor your blood work as you progress through your weight-loss journey. 

The country you live in will determine what tests are or are not covered by funding. Coverage is also dependent upon what type of health care provider ordered the blood work (medical doctor, naturopathic doctor, nurse practitioner, etc.). Access to insurance may also be a factor in the costs associated with certain blood tests. However, one thing to keep in mind is that there is no greater investment than investing in yourself (if you can afford it). That being said, just making the changes recommended by The Livy Method is a great investment into your health. 

Finally, although blood testing can provide important information about your health, it does not always give enough information. If you have had blood work done, you may need other types of tests before your health care provider can provide a more detailed picture of your health. 

*For the purposes of this post, blood test values will not be discussed, as value norms may vary from lab to lab, differ depending on age and sex and may be measured differently throughout the world (i.e., Canada compared with the United States). It is also very important to review your results with a health care provider. Be an advocate for yourself!

What happens during a blood test?

A health care provider, such as a nurse or lab professional (known as a phlebotomist), will take a sample of your blood. This is also called a blood draw. When a blood draw is taken from a vein, it is known as venipuncture, which is the most common way to take a test. A less common way to take a blood sample is with a finger prick test (this test is done by pricking your fingertip to obtain a small amount of blood). Finger-prick testing is often used for at-home test kits and rapid tests. Rapid tests are easy-to-use tests that provide very fast results and require little or no special equipment. Occasionally, (but less commonly), you may need blood drawn from an artery. This test is usually done to measure oxygen levels in your blood. Blood from arteries has a higher level of oxygen than blood from a vein, and your health care provider may need this specific information.

Preparing for a Blood Test

For some tests, you may need to fast (not eat or drink) for several hours before your test. Your health care provider will let you know if there are any special instructions to follow when preparing for your blood test. Tests require fasting Everything you eat and drink contains vitamins, proteins, nutrients or substances that can cause the levels of what you are testing for to temporarily change. 

Fasting for 8-12 hours helps ensure that blood test results are free from these variables, making your test results as accurate as possible. Your health care provider will indicate any fasting instructions required for the test(s). It is often recommended to stop eating and drinking after 8:00 PM and to arrive at the laboratory early the next morning. This way you don’t have to go too long the next day without food or drinks, which is helpful when following The Food Plan. 

Some common tests that may require fasting include: 

  • Cholesterol/lipid tests 

  • Blood sugar tests 

  • Liver function tests 

  • Kidney function tests 

  • Basic metabolic panel 

  • Glucose tests 

Check out this article that discusses fasting in more detail. 

Medications and Supplements

If taking medications, it is advised to keep taking them as prescribed before your blood test, but be sure to discuss this with your health care provider. You may also want to inform the person drawing your blood test about your medications for their reference. Some medicines can affect blood test results, but your health care provider can take this into account when interpreting your results. Stopping your medications could potentially cause more harm to you, so this would be an important discussion to have with your health care provider. 

Taking certain supplements, vitamins and/or minerals can falsely elevate or interfere with testing and can give misleading results. This is more likely with supplements, as many supplements are provided in a higher dose form. Taking supplements (such as vitamin D, vitamin C, vitamin B’s (especially biotin), iron, calcium, magnesium, etc.) before a blood test can give inaccurate results or prevent the proper diagnosis of other medical issues. Discuss your use of supplements with your health care provider to create a plan of what supplements you may need to stop until you’ve had your blood test and how far in advance you may need to do so.

The Intake of Water Before a Blood Test

In most cases, you will be able to drink water when having fasted blood work. Being well-hydrated can help with the blood test. As our blood is roughly 50% water, being well-hydrated also hydrates our veins. This creates “plumper” veins, making it easier for the phlebotomist to find them. As a result, this can allow for a smoother blood draw. Being well-hydrated will also help keep your blood pressure from dropping. As The Livy Method promotes good hydration, you are already one step ahead. 

However, can drinking too much water interfere with blood work results and cause “dilutional” and otherwise inaccurate results? This is an important consideration. Upon a literature search, it was found that there is little research on this topic. However, a study by Silvia F. Benozzi, S., Unger, G., Campion, A., & Pennacchiotti, G. (2018) examined the effects of 300 ml water intake 1 hour before phlebotomy on specific lab tests. This study was conducted because there were no current available recommendations specifying the maximum water intake volume permitted during the fasting period before the phlebotomy procedure. Although it was a very small study of 20 women aged 24-50 years of age, they found that having 300 ml of water before their blood test analysis in the study did not yield any significant effects. This being said, this study is very limited, so drinking a large volume of water before a blood test may have an impact on certain lab test results. 

Be sure to clarify with your health care provider what and how much you can drink before your test.


It is advised to refrain from exercise before a blood test. A workout can negatively impact blood test results. For the most accurate blood test results, your blood should be drawn when you are rested. 

A workout before a fasting blood test can alter the results of cholesterol and glucose tests. It may cause LDL cholesterol levels (the “bad” cholesterol) to increase and cause glucose to lower or increase, depending on the intensity and stress on the body induced by the exercise. 

Although exercise improves an overall blood panel, it is recommended to hold off on that workout until you have had your tests.


In general, having alcohol the night before should not affect your blood test results. If you begin fasting 12 hours before the test (including alcohol), it will most likely be metabolized, as long as you keep it to a drink or two. However, if the panel is specific to your liver enzymes, they may be altered. Your best bet is to ask your health care provider, but it may be better to just leave it out until you have had your test.

What's the typical blood work procedure?

A nurse or phlebotomist usually performs the blood test at a laboratory or in a medical office. The procedure takes just a few minutes. 

To perform a blood test, the nurse or phlebotomist: 

  1. Cleans the area on your arm where they’ll draw the blood from 

  1. Ties a rubber band to your upper arm to help make your veins more visible and asks you to make a fist 

  1. Puts a needle attached to a tube gently into a vein to draw blood 

  1. Removes the needle from the skin and takes the rubber band off your arm when the collection is complete 

  2. Covers the drawing site with a bandage or clean cotton and medical tape

Are there any risks to the test?

There is very little risk to having a finger-prick test or venipuncture. During venipuncture, you may have slight pain or discomfort when the needle goes in or after, but most symptoms go away quickly. There may be bruising at the spot where the needle was inserted. Some individuals may have a fear of needles or blood. This may result in anxiety or fainting during the procedure. Be sure to inform the nurse or phlebotomist if you have any fear of needles or any history of fainting. It is rare that an individual will faint from blood loss or that the procedure may result in a vein puncture or infection. Collecting blood from an artery is more painful than collecting it from a vein, but complications are rare. You may have some bleeding, bruising or soreness at the spot where the needle was inserted, and you should avoid lifting heavy objects for 24 hours after the procedure.

Types of Blood Tests that can Give you Insight into Your Health

  1. Complete Blood Count

  • A routine complete blood count (CBC) checks for levels of 10 different components of every major cell in your blood: white blood cells, immature white blood cells, red blood cells and platelets. Important components that this test measures include red blood cell count, hemoglobin, hematocrit and mean corpuscular volume (MCV). 

  • Red blood cell level abnormalities could be a sign of dehydration, anemia (iron deficiency) or bleeding. Red blood cells carry oxygen from your lungs to the rest of your body. 

  • White blood cell level abnormalities could be a sign of infection, blood cancer or an immune system disorder. White blood cells are part of your immune system, which fights infections and diseases. 

  • Platelet level abnormalities may be a sign of a clotting disorder or a bleeding disorder. Platelets are blood cell fragments that help your blood clot. They stick together to seal cuts or breaks on blood vessel walls and stop bleeding. You may have an abnormally low number if you’re on chemotherapy, take certain medications or have had a large blood transfusion. Other causes of a low platelet count are celiac disease, vitamin K deficiency and leukemia. Anemia, primary thrombocythemia or chronic myelogenous leukemia (CML) may cause an abnormally high number of platelets. 

  • Hemoglobin levels that are lower than normal may be a sign of anemia, sickle cell disease or thalassemia. Hemoglobin is an iron-rich protein in red blood cells that carries oxygen. 

  • Hematocrit levels that are too high could indicate dehydration. Low hematocrit levels may be a sign of anemia. Hematocrit is a measure of how much space red blood cells take up in your blood. 

  • Mean corpuscular volume (MCV) levels that are lower than normal may be a sign of anemia or thalassemia. MCV is a measure of the average size of your red blood cells.

2. Basic Metabolic Panel (BMP) or a Comprehensive Metabolic Panel (CMP)

A basic metabolic panel (BMP) usually checks for levels of eight compounds in the blood, whereas a comprehensive metabolic panel checks 14 compounds. A CMP tests for everything a BMP tests for but also includes a metabolic panel. A metabolic panel provides important information about your body’s chemical balance and metabolism. Metabolism is the process of how the body uses food and energy.

A BMP Includes Tests for:  

  • Glucose 

  • Calcium 

  • Sodium, potassium, chloride 

  • Bicarbonate 

  • Blood urea nitrogen (BUN) and creatinine 

A CMP includes tests for the following: 

  • Glucose (random)- a type of sugar and your body’s main source of energy. A blood glucose or blood sugar level is the most direct test to screen for diabetes and is also used in diabetes management. This is typically a blood sugar that is taken at a random time, with no restriction on eating or drinking. 

  • Calcium- one of the body’s most important minerals. This mineral is essential for the development and maintenance of healthy bones and teeth. Calcium is also essential for the proper functioning of your nerves, muscles and heart. 

  • Sodium, potassium, carbon dioxide and chloride- these are electrolytes, electrically charged minerals that help control the amounts of fluids, electrical activity of nerves and muscles and the balance of acids and bases in your body. 

  • Albumin- a protein made in the liver and one of the major proteins essential for the healthy function of the liver and kidney. 

  • Total protein- measures the total amount of protein in the blood. This test assists in determining liver and kidney function, as well as nutritional health. 

  • ALP (alkaline phosphatase)- an enzyme mostly found in the bones and liver that’s involved in several bodily processes. This test can help detect bone disorders and liver disease. 

  • ALT (alanine transaminase)- an enzyme found in the liver. Abnormalities may indicate liver disease. 

  • AST (aspartate aminotransferase)- an enzyme found in the liver and other tissues within the body. An elevated level can be an indication of hepatitis. 

  • Bilirubin- is a waste that results from the breakdown of red blood cells in the body that the liver filters out. High concentrations may result in jaundice and may indicate an issue such as hepatitis, sickle cell anemia, cirrhosis, alcohol and drug abuse. 

  • BUN (blood urea nitrogen) and creatinine- waste products removed from your blood by your kidneys. An elevation in these may indicate renal issues. 

This test may require you to fast before your blood is drawn, depending on the instructions of your health care provider and what the test is measuring. Your health care provider may perform follow-up tests to confirm a diagnosis.

3. Glomerular Filtration Rate (GFR) Test

Using some of the blood work obtained from the BMP or CMP, your health care provider can calculate something called a glomerular filtration rate (GFR). This is a blood test that checks how well your kidneys are working. Your kidneys have tiny filters called glomeruli which help remove waste and excess fluid from the blood. A GFR test estimates how much blood passes through these filters each minute. 

A GFR can be measured directly, but it is a complicated test requiring specialized providers. The GFR is most often estimated using a test called an estimated GFR or eGFR. To get an estimate of your GFR, your health care provider will use a method known as a GFR calculator. A GFR calculator is a type of mathematical formula that estimates the rate of filtration. It does this by comparing the results of a blood test that measures creatinine and other specific factors. This information includes some or all of the following: your creatinine level, age, weight, height, gender and race. 

A GFR test is used to help diagnose kidney disease at an early stage (when it is most treatable), and may also be used to monitor people with chronic kidney disease (CKD) or other conditions that cause kidney damage. These include diabetes and high blood pressure.

4. Fasting Blood Sugar

This is often a test used to screen for diabetes and requires fasting.

5. A1C

The A1C test (also known as the hemoglobin A1C or HbA1c test) is a simple blood test that measures your average blood sugar levels over the past 3 months. It is one of the most commonly used tests to diagnose prediabetes and diabetes and is also the main test used to manage diabetes. Higher A1C levels are linked to diabetes complications, so reaching and maintaining your individual A1C goal is very important if you have diabetes. 

What does the A1C test measure?

When sugar enters your bloodstream, it attaches to the hemoglobin, a protein in your red blood cells. Everybody has some sugar attached to their hemoglobin, but people with higher blood sugar levels have more. The A1C test measures the percentage of your red blood cells that have sugar-coated hemoglobin. 

Several factors can falsely increase or decrease your A1C result, including: 

  • Kidney failure, liver disease or severe anemia 

  • A less common type of hemoglobin that people of African, Mediterranean or Southeast Asian descent and people with certain blood disorders (such as sickle cell anemia or thalassemia) may have 

  • Certain medicines, including opioids and some HIV medications 

  • Blood loss or blood transfusions 

  • Early or late pregnancy 

Let your health care provider know if any of these factors apply to you and ask if you need additional follow-up tests.

6. Lipid Panel

A lipid panel is a blood test that measures the amount of specific fat molecules called lipids in your blood. In most cases, this panel includes four different cholesterol measurements and a measurement of your triglycerides. 

Having too many lipids (cholesterol and triglycerides) in your blood can lead to build-up in your blood vessels and arteries, which can cause damage and increase your risk of cardiovascular problems. Because of this, health care providers use lipid panels for both children and adults to evaluate the risk of cardiovascular diseases like heart disease, heart attack (myocardial infarction) and stroke. 

A lipid panel measures five different types of lipids from a blood sample, including: 

  • Total cholesterol- This is your overall cholesterol level - the combination of LDL-C, VLDL-C and HDL-C. 

  • Low-density lipoprotein (LDL) cholesterol- This is the type of cholesterol that is known as “bad cholesterol.” It can collect in your blood vessels and increase your risk of cardiovascular disease. This build-up is known as plaque. 

  • Very low-density lipoprotein (VLDL) cholesterol- This is a type of cholesterol that’s usually present in very low amounts when the blood sample is a fasting sample, as it mostly comes from the food you have recently eaten. An increase in this type of cholesterol in a fasting sample may be a sign of abnormal lipid metabolism. 

  • High-density lipoprotein (HDL) cholesterol- This is the type of cholesterol that is known as “good cholesterol.” HDL is considered “good” because it helps decrease the build-up of LDL cholesterol in your blood vessels and helps the liver break them down into waste. 

  • Triglycerides- This is a type of fat from the food we eat. Excess amounts of triglycerides in your blood are associated with cardiovascular disease and pancreatic inflammation. 

*A great way to remember the differences between LDL and HDL cholesterol is the “L” in LDL stands for “lousy” and the “H” in HDL stands for “healthy.” 

You may need to fast before this test.

7. Thyroid Panel

Your thyroid is a tiny gland in your neck. It helps regulate bodily functions, like your mood, energy level and overall metabolism. A thyroid panel, or thyroid function test, checks how well your thyroid is producing and reacting to certain hormones, such as: 

  • Thyroid-stimulating hormone (TSH)- is produced in the pituitary gland and regulates the balance of thyroid hormones, including T4 and T3, in the bloodstream. This is usually the first test your provider will do to check for thyroid hormone imbalance. Most of the time, thyroid hormone deficiency (hypothyroidism) is associated with an elevated TSH level, while thyroid hormone excess (hyperthyroidism) is associated with a low TSH level. If TSH is abnormal, measurement of thyroid hormones directly, including thyroxine (T4) and triiodothyronine (T3) may be done to further evaluate the problem. 

  • T4: thyroxine- tests for hypothyroidism and hyperthyroidism, and used to monitor treatment of thyroid disorders. Low T4 is seen with hypothyroidism, whereas high T4 levels may indicate hyperthyroidism. 

  • FT4: Free T4 or free thyroxin- is a method of measuring T4 that eliminates the effect of proteins that naturally bind T4 and may prevent accurate measurement. 

  • T3: triiodothyronine- tests help diagnose hyperthyroidism or show the severity of hyperthyroidism. Low T3 levels can be observed in hypothyroidism, but more often this test is useful in the diagnosis and management of hyperthyroidism, where T3 levels are elevated. 

  • FT3: Free T3 or free triiodothyronine- is a method of measuring T3 that eliminates the effect of proteins that naturally bind T3 and may prevent accurate measurement. 

Abnormal levels of these hormones can indicate: 

  • Low protein levels 

  • Thyroid growth disorders 

  • Abnormal levels of testosterone or estrogen 

These tests alone are not meant to diagnose any illness but may prompt your health care provider to do additional testing to evaluate for a possible thyroid disorder.

8. Cardiac Biomarkers

Enzymes are proteins that help your body accomplish certain chemical processes, such as breaking down food and clotting blood. They are used throughout your body for many vital functions. Abnormal enzyme levels can indicate many conditions. 

Common enzymes tested include: 

Creatine kinase (CK)- is an enzyme primarily located in the brain, heart and skeletal muscle. When muscle damage happens, CK seeps into the blood in growing amounts. SCIENCE GUIDE 419 

Creatine kinase-MB (CK-MB)- are enzymes found in your heart. They often increase in your blood after a heart attack or other heart injury. 

Troponin- is a heart enzyme that can leak into your blood and result in heart injury.

9. Coagulation Panel

Coagulation tests measure how well your blood clots and how long it takes for your blood to clot. Clotting is a crucial process that helps you stop bleeding after a cut or wound. But a clot in a vein or artery can be deadly since it can block blood flow to your brain, heart or lungs. This can cause a heart attack or stroke. 

Coagulation test results vary based on your health and any underlying conditions that may affect clotting. 

  • Complete blood count (CBC) and platelet count- your health care provider may order a CBC as part of your routine physical. The results of the test can alert your doctor if you have anemia or a low platelet count, which can interfere with your ability to clot. The CBC and platelet count are discussed at the beginning of this post. 

  • Factor V assay- this test measures Factor V, a substance involved in clotting. An abnormally low level may be indicative of liver disease, primary fibrinolysis (a breakdown of clots) or a condition known as disseminated intravascular coagulation (DIC). 

  • Fibrinogen level- fibrinogen or Factor I is a blood plasma protein made by your liver and one of the 13 coagulation factors that are involved in normal blood clotting. This test measures how much fibrinogen is in your blood. Abnormal results may be a sign of excessive bleeding or hemorrhage, or fibrinolysis. Fibrinolysis is a normal body process that prevents blood clots that occur naturally from growing and causing problems. Primary fibrinolysis refers to the normal breakdown of clots. Secondary fibrinolysis is the breakdown of blood clots due to a medical disorder, medicine or other cause. 

  • Prothrombin time (PT or PT-INR)- prothrombin is another protein your liver produces. The prothrombin time (PT) test measures how well and how long it takes your blood to clot. It normally takes about 25-30 seconds. It may take longer if you take blood thinners. Other reasons for abnormal results include hemophilia, liver disease, vitamin K deficiency and small intestinal malabsorption. It’s also useful in monitoring those who take medications that affect clotting, such as warfarin (Coumadin). Results are given in the number of seconds it takes the blood to clot. Sometimes the PT test uses a calculation called the international normalized ratio (INR) to compare the results of different laboratories. Your health care provider will usually order the PT test along with another clotting test called an activated partial thromboplastin time (aPTT). 

Thrombin time- thrombin time measures how well fibrinogen is working. Abnormal results may be due to inherited fibrinogen disorders, liver disease, some cancers and medications that affect clotting.

10. DHEA-Sulfate Serum Test

The dehydroepiandrosterone (DHEA) hormone comes from your adrenal glands. This test measures whether it’s too high or too low. 

In men, DHEA helps develop traits like body hair growth, so low levels are considered abnormal. In women, high levels can cause traits that are typically male, like excess body hair to develop, so low levels are normal. 

Low levels may be caused by: 

  • Addison’s disease 

  • Adrenal dysfunction 

  • Hypopituitarism 

High levels in men or women can result from: 

  • Congenital adrenal hyperplasia 

  • Benign or malignant tumor on the adrenal gland 

  • Polycystic ovary syndrome (PCOS) 

  • Ovarian tumor

11. C-Reactive Protein Test

A c-reactive protein test measures the level of c-reactive protein (CRP) in your blood. CRP is a protein made by your liver that is sent into your bloodstream in response to inflammation. Inflammation is your body’s way of protecting your tissues if you have been injured or have an infection. It can cause pain, redness and swelling in the injured or affected area. Some autoimmune disorders and chronic diseases can also cause inflammation. 

Normally, you have low levels of c-reactive protein in your blood. High levels may be a sign of a serious infection or other disorder. A CRP test may be used to find or monitor conditions that cause inflammation. These include: 

  • Bacterial infections such as sepsis (blood infection)- a severe and sometimes life-threatening condition 

  • A fungal infection 

  • Inflammatory bowel disease- a disorder that causes swelling and bleeding in the intestines 

  • An autoimmune disorder such as lupus or rheumatoid arthritis 

  • An infection of the bone called osteomyelitis 

  • Inflammation in the arteries of the heart can mean a higher risk of heart attack 

If your results show a high level of CRP, it probably means there is some inflammation in your body. A CRP test does not explain the cause or location of the inflammation. Therefore, if your results are not within the normal range, your health care provider may order more tests to figure out why you have inflammation. Factors that can raise CRP levels include cigarette smoking, obesity and a lack of exercise. 

A CRP test is sometimes confused with a high-sensitivity-(hs) CRP test. Although they both measure CRP, they are used to diagnose different conditions. A hs-CRP test measures much lower levels of CRP. It is used to assess an individual’s risk of heart disease and stroke.

Testing for Vitamin and Mineral Deficiencies

12. 25-Hydroxy Vitamin D Test

Vitamin D influences many organ systems, but it primarily increases calcium and phosphate absorption from the intestine and promotes normal bone formation and mineralization to help maintain strong bones and teeth. In children, vitamin D helps fuel the growth of healthy bones and teeth. As we age, it helps prevent osteoporosis (decreased bone mass), which leads to an increased risk of fractures. 

Often known as the “sunshine vitamin”, vitamin D is produced by your body when the sun’s UV rays (ultraviolet B radiation) come in contact and is absorbed through your skin. It does not occur naturally in many foods, but it can be found in fish liver oils and saltwater fish, eggs and fortified dairy or by taking vitamin supplements. It is estimated that up to one-third of Canadians do not have the recommended levels of vitamin D. 

Your ability to produce vitamin D is greatly impacted by: 

  • Geography 

  • The season/weather 

  • Sunscreen usage 

  • Skin pigment 

  • Age 

Your ability to absorb vitamin D from your diet or supplements may be impacted by: 

  • Malabsorption syndromes, such as fat malabsorption or gastric bypass surgery 

Several factors can increase your risk of vitamin D deficiency such as: 

  • Not consuming enough foods that are rich in vitamin D. This is likely if you do not eat fish, follow a strict vegan diet or are lactose-intolerant. 

  • Not getting enough safe exposure to the sun. This can be caused by geography, the weather, sunscreen usage and even skin pigment. Vitamin D levels may decrease with age because skin synthesis declines. Sunscreen use and dark skin pigmentation also reduce skin synthesis of vitamin D. 

  • You have kidney issues that prevent vitamin D from being converted to its active form in your body. This happens mostly within older age groups. 

  • Certain medical problems can affect your ability to absorb vitamin D, such as Crohn’s disease, cystic fibrosis and celiac disease. Certain people with obesity can also have vitamin D deficiency, since vitamin D is extracted from the blood by fat cells, altering its release into the circulation. 

Vitamin D has 2 main forms: 

  • D2 (ergocalciferol) 

  • D3 (cholecalciferol) is the naturally occurring form that is synthesized by the body through exposure to the skin by UV B rays from the sun, and the form used for low-dose supplementation.

13. Vitamin B-12

Vitamin B12 is an important nutrient that helps your body keep your nerve cells healthy and is required in the production of red blood cells. It also helps your body make DNA, the genetic material in all of your cells. Your body does not make vitamin B12 on its own, so you have to consume food and beverages that contain vitamin B12 to acquire it. Vitamin B12 is found in animal products, such as meat, dairy and eggs. It can also be found in fortified foods (foods that have certain vitamins and nutrients added to them), such as certain cereals, bread, soy and nutritional yeast. 

What is vitamin B12 deficiency and B12 deficiency anemia? 

Vitamin B12 deficiency happens when your body is either not getting enough or not absorbing enough vitamin B12 from the food that you eat in order to function properly. 

Vitamin B12 deficiency can cause physical, neurological and psychological problems if it is not treated. 

Vitamin B12 deficiency anemia happens when your body is not producing enough healthy red blood cells because of a vitamin B12 deficiency. It is important to note that people can still have a vitamin B12 deficiency without having anemia. 

Situations or conditions that can cause vitamin B12 deficiency include: 

  • Lack of vitamin B12 in your diet: People who do not eat enough foods that naturally have vitamin B12 or do not eat foods fortified with vitamin B12 can develop vitamin B12 deficiency. 

  • Gastritis: Gastritis is inflammation of the stomach lining, and it is a common cause of vitamin B12 deficiency. It can cause vitamin B12 deficiency due to a lack of hydrochloric acid or HCl in your stomach, which is needed for vitamin B12 absorption. 

  • Pernicious anemia: People who have pernicious anemia, a rare medical condition, are not able to make intrinsic factors, a protein made by your stomach. You need intrinsic factors so that your body can absorb vitamin B12. People with pernicious anemia have a vitamin B12 deficiency. 

  • Digestive diseases: Diseases that affect the digestive system, like Crohn’s disease and celiac disease, can prevent the body from fully absorbing vitamin B12. 

  • Surgery: People who have had gastrointestinal surgery, such as a gastric bypass, can have difficulty absorbing vitamin B12. 

  • Alcohol use disorder: This condition can damage the digestive system and cause vitamin B12 deficiency. 

  • Transcobalamin II deficiency: This is a rare genetic disorder that impairs the transport of vitamin B12 (also known as cobalamin) within the body. 

The tests used to diagnose vitamin B12 deficiency are a complete blood count (CBC) and a vitamin B12 blood test level.

14. Ferritin Blood Test (Part of an Iron Profile)

A ferritin blood test measures the level of ferritin in your blood. Ferritin is a protein that stores iron inside your cells. Iron is an important mineral required in the formation of healthy red blood cells. Red blood cells carry oxygen from your lungs to the rest of your body. Iron is also important for healthy muscles, bone marrow and organs, including brain development in children. 

Too little or too much iron in your body can cause serious health problems if not treated. A ferritin blood test can show how much iron you have stored in your body. 

What is it used for? 

A ferritin blood test is used to help check your iron levels. It can help your health care provider find out if your body is storing the right amount of iron to stay healthy. 

The test may also be used to help diagnose or rule out conditions related to iron levels, including: 

  • Hemochromatosis- having too much iron in your body (also called iron overload) 

  • Iron deficiency anemia- having too few red blood cells because of a lack of iron 

  • Liver diseases- much of the ferritin in your body is stored in your liver 

  • Restless legs syndrome- a tingling or burning feeling in your legs that may be caused by a lack of iron 

  • Adult Still disease(also called adult-onset Still disease or AOSD)- is an uncommon disease that causes joint pain, fever and rash, often with high ferritin levels 

  • Monitoring chronic (long-lasting) conditions- that may affect your iron levels, such as cancer, kidney disease and autoimmune diseases 

  • Iron treatment- If you are being treated for iron issues, the test may be used to check how well the treatment is working. 

You may need to fast for this test and may also need this test if the results of a CBC show that you have low hematocrit or hemoglobin levels. Iron levels are highest in the morning, so a morning test is recommended.

Other Tests for Consideration Hormone Testing

Although not typically ordered in baseline blood tests, hormones (such as insulin, aldosterone, cortisol, estrogen, estradiol, testosterone, progesterone, follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin, renin, norepinephrine/epinephrine and adrenal hormones) are closely associated with the body’s metabolism and may be a consideration if weight loss is an issue. Testing for the levels of these hormones can enable the detection of an underlying endocrinological reason for obesity and maybe something to consider down the road. 

The glands that make up the endocrine system produce chemical messengers called hormones that travel through the blood to other parts of the body. 

The endocrine system includes important glands such as the pituitary, thyroid, parathyroid, thymus and adrenal glands. 

The pancreas, ovaries and testes are other glands that contain endocrine tissue and secrete hormones. 

Finally, other blood tests that may be considered are vitamin K levels, metals (such as copper, zinc, mercury, etc.) and uric acid. However, there is truly a plethora of blood tests available to be ordered if needed, and well beyond the scope of this post. 

Now that you have a better understanding of many of the tests involved in checking your baseline health, let’s talk about the process of acquiring these blood tests.

Who orders my blood tests?

Your health care provider typically orders blood tests for you during a physical, checkup or an appointment intended to screen for a specific condition. 

It’s possible to order your blood tests online without a health care provider, but health insurance may not cover these tests. While such blood tests may be more accessible and convenient, it may be harder to interpret the results without a medical professional reviewing and discussing them with you. Also, some blood testing facilities may not give you accurate results. It’s best to partner with your health care provider and healthcare team.

Where can I get blood work done?

  • Point-of-care. This describes situations when you can get a blood test wherever you are receiving medical care. This is typically at your health care provider’s office during an appointment. 

  • Private laboratories. Hospitals may use private labs to offload some testing from their laboratories or in cases when a specialized test is needed. In some situations, health insurance plans may require you to use a specific laboratory that is in their network for the test to be covered. 

  • Home testing. In some situations, you may be able to acquire certain tests at a pharmacy and then do the testing at home. You may need a prescription for some tests, while others may be available over the counter. This can include things like blood glucose monitoring for people with diabetes or the fecal occult blood test that screens for colorectal cancer. In the US, the Food and Drug Administration (FDA) must approve all home tests before they are available for purchase. In Canada, legitimate tests must be licensed by Health Canada. 

In summary, although you may be wondering what blood tests you should be asking for to assess your baseline health, this is very individual and specific to your health and health history. Not all tests are needed for all people. It is a discussion that needs to be discussed with your health care provider, which is a part of self-advocacy. 

In Ontario, for example, it is reasonable when having a general health assessment by a family doctor to be able to have your blood tested and covered for: a CBC, electrolytes, BUN/creatinine/GFR, cholesterol, blood glucose (fasting or random), coagulation profile, albumin, liver function tests, iron profile and thyroid function tests. However, if medically indicated, you may have more investigative testing, which is usually covered. Vitamin D and prostate-specific antigen or PSA (for prostate cancer screening), for example, are not covered. 

If seeing a Naturopathic Doctor, you may have a more expansive panel for a general health assessment but you will likely need to pay out of pocket if not covered with personal health insurance. This is when one decides on the importance of investing in their health, if they are financially able. 

Hopefully, you have a better understanding of the different baseline blood work tests discussed, which can give you greater insight into your health and may result in you feeling more empowered as you progress through your weight loss journey.


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