Vitamin D3: You Can Have Too Much of a Good Thing

Vitamin D3 is an essential vitamin that reinforces several bodily processes when it is taken in moderation. Many people become vitamin D deficient for a number of reasons, including inadequate vitamin D intake from food, reduced exposure to sunlight, and certain health issues [1]. In such cases, a doctor may recommend high servings of vitamin D ranging from 5,000 to 10,000 IUs, but large amounts do not always guarantee health benefits.

KD Ultra is a premium dietary supplement consisting of vitamins D3, K1, and K2. Each serving (one capsule) provides 2500 IU of vitamin D3, which is 312% of the recommended daily allowance (RDA). This serving is ideal for boosting vitamin D levels if a deficiency develops and helping to maintain optimal levels in the body [1, 2]. Furthermore, vitamin D3 demonstrates superior activity in comparison to vitamin D2, which is less potent and not as efficient at boosting vitamin D levels in the body [3, 4]. Vitamin D3 also has a longer half-life and is more stable than vitamin D2 [3, 4].

In addition to providing a bountiful serving in the most beneficial form, this exclusive supplement offers a vegan form of vitamin D3 naturally sourced from wild harvested reindeer lichen – a nutritional advantage not offered by most vitamin D supplements on the market.

Consumers who experience a vitamin D deficiency can take more than one capsule to increase their intake, but it is important to be aware of the role additional nutrients play in influencing vitamin D levels and activity.

Nutrients that Support Healthy Vitamin D Status

Magnesium, the second most abundant mineral in the body, plays a key role in the production and utilization of vitamin D [5]. More specifically, magnesium levels influence the activity of three important enzymes that regulate vitamin D levels as well as vitamin D binding protein [5]. Research even shows that a magnesium deficiency leads to poor vitamin D levels and resistance to vitamin D supplementation [5, 6 ]. On the other hand, high magnesium intake through the diet or supplementation is associated with a dramatically lower risk of vitamin D deficiency [6]. This means the body’s ability to efficiently produce and metabolize vitamin D is directly influenced by the level of magnesium in the body.

Furthermore, magnesium exerts a similar influence on calcium status, with studies showing that low magnesium levels minimize the release of parathyroid hormone (PTH) [7]. This issue subsequently lowers calcium levels because PTH production helps regulate calcium metabolism and balance [7]. The influence of magnesium is so powerful that low levels of this particular mineral can even disrupt the interaction between vitamin D and calcium. One of vitamin D’s primary functions is to raise levels of calcium and phosphorus as these nutrients work together to promote strong bones [8]. As demonstrated through research, low magnesium is linked to poor vitamin D, PTH, and calcium levels [6, 7].

Research also shows that vitamins K and D work synergistically to support both bone and heart health by influencing the transport of calcium away from the wall of the arteries and instead towards the bones [9, 10]. Excessive calcium buildup in the arterial walls, also known as calcification, can disrupt arterial wall flexibility, disrupt blood flow, and increase the heart's workload [11]. Arteries supply the heart with nutrient-rich blood, and healthy levels of vitamin K promote proper calcium metabolism that helps maintain the elasticity of the arterial walls.

Regular vitamin K intake also heightens the activity of specific proteins that target and redirect calcium to minimize the amount of calcium that can travel into the walls of the arteries [10]. This process enhances heart function and bone health by reinforcing optimal nutrient transfer and blood circulation. However, these benefits are much more pronounced when vitamins K1 and K2 are consumed. KD Ultra provides a healthy serving of K vitamins (K1-100 mcg and K2-1600 mcg) and vitamin D3 (2500 IU) that support optimal use of these essential vitamins.

Overall, these findings indicate that in the absence of healthy magnesium and vitamin K levels, simply increasing servings of vitamin D to extreme amounts (e.g., 10,000 IU) to target a vitamin D deficiency doesn’t guarantee health benefits. Taking too much vitamin D can also lead to dangerous consequences.

The Dangers of Consuming Excess Vitamin D

A serious complication that may develop if excess amounts of vitamin D are consumed is calcification [12]. This health problem is the result of calcium buildup in the arterial walls, which leads to stiffening of the blood vessels, poor red blood cell function, bone-like tissue, and an increased risk of heart problems [12]. Excess vitamin D in the body raises calcium levels in the blood, allowing more of this mineral to be inadvertently transported to the arterial walls where it can lead to heart issues [1].

Consumers tend to be guided by what their doctors recommend, who often suggest calcium and vitamin D as a standard protocol for any bone-related issues. Bones are comprised of calcium, while vitamin D assists in the absorption of calcium, so naturally this seems like a good approach. However, according to a recent study published in Integrative Medicine: A Clinician’s Journal (IMCJ), this can be a dangerous combination, as increased calcium tends to bind to arteries and cause cardiovascular stiffening. The American diet is rarely deficient in calcium, but rather lacking vitamin K2. Vitamin K2 directs the transportation of calcium toward the bones and away from the walls of the arteries, making vitamin K2 and vitamin D3 an ideal combination for bone health.

Additional research shows that low magnesium levels in the presence of high vitamin D still worsens these types of health issues because adequate magnesium intake helps balance vitamin D and calcium status in the body [13]. More specifically, healthy magnesium levels boost vitamin D availability when a deficiency is developing, but also helps minimize circulating levels of vitamin D if too much is consumed [13, 14]. Therefore, the body needs carefully balanced levels of vitamin D to maintain optimal health and it is important to remember that more is not always better.


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