Vitamin D is the principle regulator of calcium homeostasis in the body. It is essential for skeletal development and bone mineralization. Vitamin D is a prohormone with no hormone activity. It is converted to a molecule that has biological activity. The active form of the vitamin is 1,25-dihydroxyvitamin D, usually referred to as vitamin D3. It is synthesized in the skin from 7-dehydrocholesterol via photochemical reactions requiring UV light (sunlight). Inadequate exposure to sunlight contributes to vitamin D deficiency. Vitamin D deficiency in adults can lead to osteoporosis. This results from a compensatory increase in the production of parathyroid hormone resulting in bone resorption. Increasing evidence is accumulating that vitamin D may also contribute to antioxidant function by inhibiting lipid peroxidation. The mechanism of the antioxidant effect is unknown. Vitamin D is also needed for adequate blood levels of insulin. Vitamin D receptors have been identified in the pancreas.

Vitamin D3 is also referred to as 1,25-hydroxyvitamin D3 (1,25-OHD3).

1,25-OHD3 has a shorter half-life in the blood than 25-OHD (what most standard labs run, and what is most commonly used to assess total vitamin D status), and, therefore, levels may differ from what is measured as 25-OHD.

The conversion of 25-OHD to 1,25-OHD is performed in D the kidneys and regulated by parathyroid hormone (PTH).

When blood calcium levels fall, PTH signals the kidneys to convert more 25-OHD to 1,25-OHD, which increases intestinal absorption of calcium, and reduces bone demineralization of calcium.

Vitamin D3 also regulates the function of hundreds of genes, supports the immune system, supports production and function of endocrine hormones, is important for normal growth and development of bones and teeth, tightly regulates the levels of calcium and phosphorus being absorbed intestinally as well as released from bone, regulates cell differentiation and growth, and may play an important role in regulating mood.

Patients who present with hypercalcemia, hyperphosphatemia, and low PTH may suffer from unregulated conversion of 25-OHD to 1,25-OHD.

Vitamin D3 is also referred to as 1,25-hydroxyvitamin D3 (1,25-OHD3).

1,25-OHD3 has a shorter half-life in the blood than 25-OHD (what most standard labs run, and what is most commonly used to assess total vitamin D status), and, therefore, levels may differ from what is measured as 25-OHD.

The conversion of 25-OHD to 1,25-OHD is performed in D the kidneys and regulated by parathyroid hormone (PTH).

When blood calcium levels fall, PTH signals the kidneys to convert more 25-OHD to 1,25-OHD, which increases intestinal absorption of calcium, and reduces bone demineralization of calcium.

Vitamin D3 also regulates the function of hundreds of genes, supports the immune system, supports production and function of endocrine hormones, is important for normal growth and development of bones and teeth, tightly regulates the levels of calcium and phosphorus being absorbed intestinally as well as released from bone, regulates cell differentiation and growth, and may play an important role in regulating mood.

Patients who present with hypercalcemia, hyperphosphatemia, and low PTH may suffer from unregulated conversion of 25-OHD to 1,25-OHD.

Vitamin E is an antioxidant that protects cell membranes and other fat-soluble compounds from oxidative damage by free radicals.

Vitamin E, particularly in the form of alpha-tocopherol, is a critical antioxidant that helps protect cells from oxidative stress, supports cardiovascular and immune health, and prevents various conditions related to oxidative damage. Monitoring its levels through lab testing can be important for individuals with malabsorption disorders, poor dietary intake, or those at risk of oxidative stress-related diseases. Optimal vitamin E levels are essential for maintaining overall health and preventing potential complications.

Vitamin E is a family of eight related compounds, including four tocopherols and four tocotrienols. While alpha-tocopherol is the main form found in human tissues, gamma-tocopherol is the most common form in the U.S. diet, especially from soybean and corn oils. In contrast, European diets, which rely more on olive and sunflower oils, contain much less gamma-tocopherol—leading to significantly lower blood levels compared to Americans.

Vitamin E acts as a fat-soluble antioxidant, protecting cell membranes and polyunsaturated fatty acids from free radical damage. Gamma-tocopherol contributes to this defense, though it can be reduced when alpha-tocopherol is taken in high amounts through supplementation. Including multiple forms of vitamin E in the diet—through foods like nuts, seeds, and vegetable oils—supports a more complete antioxidant balance.

Vitamin E is an important antioxidant that reduces the formation of reactive oxygen species (ROS) that result from fat oxidation.

Vitamin E also regulates cell signaling, influences immune function, and inhibits coagulation.

A vitamin E test measures the amount of vitamin E in your blood. Vitamin E (also known as tocopherol or alpha-tocopherol) is a nutrient that is important for many body processes. It helps your nerves and muscles work well, prevents blood clots, and boosts the immune system. Vitamin E is a type of antioxidant, a substance that protects cells from damage.

Vitamin E is an important antioxidant that reduces the formation of reactive oxygen species (ROS) that result from fat oxidation.

Vitamin E also regulates cell signaling, influences immune function, and inhibits coagulation.

Vitamin E, particularly its beta and gamma tocopherol components, is a highly beneficial nutrient well-regarded for its antioxidant properties and vital role in maintaining overall health. As one of the eight forms of Vitamin E, beta-gamma tocopherol stands out for its potent ability to neutralize harmful free radicals in the body, thus playing a critical role in preventing oxidative stress, a key factor in the development of chronic diseases. This form of Vitamin E is essential for immune system function, skin health, and the prevention of inflammation-related disorders. It is naturally found in a variety of foods including nuts, seeds, and vegetable oils, making it easily accessible through a balanced diet.

Vitamin K is a fat-soluble vitamin crucial for blood clotting, bone health, and cardiovascular function. Assessing Vitamin K status is complex, as there is no single gold-standard biomarker. Several biomarkers are used to evaluate Vitamin K levels, each with its own strengths and limitations.

Vitamin K1 is essential for blood clotting and bone health, and you can get it from various plant-based foods like leafy greens.

Vitamin K is a group of fat-soluble vitamins. This group of vitamins includes two natural vitamins: vitamin K1 and vitamin K2. These Vitamins are structurally similar and their name comes from the German word “klotting”.

Vitamin K1, is also known as phylloquinone.

Vitamin K assists with blood clotting, supports the K formation of bone and bone matrix, and aids in
glucose to glycogen conversion for storage in the
liver.

The primary function of vitamin K is to aid in the formation of clotting factors and bone proteins. It serves as a cofactor in the production of six proteins that regulate blood clotting, including prothrombin. In addition, it helps to form osteocalcin, a protein necessary for the mineralization of bone.

Vitamin K also aids in the formation of glucose into glycogen for storage in the liver. In addition, it promotes the prevention and reversal of arterial calcification, plague progression and lipid peroxidation. Deficiency may increase the risk of calcification of arterial walls, particularly in individuals on vitamin D supplementation (Vitamin D promotes calcium absorption). Vitamin K exists in three forms: K1, a natural form found in plants (phylloquinone); K2, which is synthesized in the intestine (menaquinone); and K3, a synthetic form that must be activated in the liver (menadione).

Vitamin K is absorbed in the upper small intestines and transported throughout the body in chylomicrons.

Vitamin K is a group of fat-soluble vitamins. This group of vitamins includes two natural vitamins: vitamin K1 and vitamin K2.

Vitamin K2 is the main storage form of Vitamin K in animals. It has several forms, referred to as menaquinones.

The nomenclature denoting vitamin K2 types will include an‘MK’to specify this is a menaquinone and the number following this denotes how many isoprenyl units are on the side chain of the molecule. The most common forms are MK-4 and MK-7.

Bacteria in the colon can convert K1 (from K plant-based foods) into vitamin K2.

Vitamin K2 is necessary to prevent arterial 2 calcification, which it does by activating matrix GLA
protein (MGP). This matrix GLA protein is present in blood vessels and inhibits soft tissue calcification.

Matrix GLA protein needs to be carboxylated to work properly and Vitamin K2-MK7 plays a major role in this carboxylation.

Vitamin K is a group of fat-soluble vitamins. This group of vitamins includes two natural vitamins: vitamin K1 and vitamin K2.

Vitamin K2 is the main storage form of Vitamin K in animals. It has several forms, referred to as menaquinones.

The nomenclature denoting vitamin K2 types will include an‘MK’to specify this is a menaquinone and the number following this denotes how many isoprenyl units are on the side chain of the molecule. The most common forms are MK-4 and MK-7.

Bacteria in the colon can convert K1 (from K plant-based foods) into vitamin K2.

Vitamin K2 is necessary to prevent arterial 2 calcification, which it does by activating matrix GLA
protein (MGP). This matrix GLA protein is present in blood vessels and inhibits soft tissue calcification.

Matrix GLA protein needs to be carboxylated to work properly and Vitamin K2-MK7 plays a major role in this carboxylation.

Very-low-density lipoprotein (VLDL) is a type of lipoprotein produced by the liver that plays a key role in transporting triglycerides, a form of fat, through the bloodstream to be used or stored by the body. VLDL is considered a type of “bad” cholesterol because high levels contribute to the formation of plaque in the arteries—a process called atherosclerosis—which increases the risk of heart disease, stroke, and other cardiovascular conditions. While similar to LDL (low-density lipoprotein), which carries mostly cholesterol, VLDL carries mostly triglycerides and is often estimated using a triglyceride measurement (typically by dividing the triglyceride level by 5). Elevated VLDL levels are associated with poor diet, obesity, sedentary lifestyle, diabetes, excessive alcohol intake, hypothyroidism, and certain medications. These particles are part of the body’s natural system for delivering fats and energy to tissues, but when present in excess, they can promote dangerous plaque buildup in the arteries. VLDL, LDL, and their remnant particles can lodge in artery walls, narrow blood vessels, and restrict oxygen-rich blood flow to the heart, brain, and other organs. High VLDL is particularly concerning when combined with other risk factors such as high LDL, low HDL (the "good" cholesterol), high blood pressure, and diabetes. Because there’s no direct test for VLDL, it’s usually assessed as part of a lipid panel, which includes total cholesterol, HDL, LDL, and triglycerides. Managing high VLDL levels often starts with lifestyle changes like reducing saturated fat and sugar intake, exercising regularly, avoiding alcohol, and addressing related conditions like obesity or insulin resistance. In some cases, medication may be necessary to help reduce cardiovascular risk. For most adults, cholesterol and lipid levels—including VLDL—should be checked every 4 to 6 years, or more often if risk factors are present.