Forgotten Fertility Nutrients

According to a recent U.S. census, birthrates have declined for six straight years, and by almost 20% in total since 2007 (2). And, in most industrialized countries, fertility rates for men and women have steadily declined since the 1950s. As with most health-related issues, the answer is likely complex and not able to be boiled down to one solution. But, I believe that a decline in the quality of our diet and nutritional status is one of the key factors. 

We know that several micronutrients are required for conception and a healthy pregnancy, including vitamins A, D, E, and, K2 and minerals like magnesium, potassium, calcium, and choline. Yet, according to recent statistics, the majority of Americans are deficient in most of these nutrients. 

What Are Fat Soluble Vitamins?

Vitamins and minerals are organic substances found in the food we eat which are essential for hundreds of roles in the body. Think of these nutrients as little ingredients that are essential to making the reactions involved in metabolism, growth and development, and other everyday functions our body performs, run smoothly and efficiently. Fat soluble vitamins (FSV) are essential organic substances that our body needs and can not make on its own and include vitamins A, D, E, and K.

These vitamins must be sourced from the food we eat and possible supplementation depending on unique needs and requirements. They are called “fat-soluble” because they require fat to be absorbed and used properly by the body. Without enough dietary fats (think avocado, grass-fed butter, ghee, etc.) these vitamins won’t be used for the creation of fertility supporting hormones and other essential fertility requirements.

FSV are stored mostly in the liver, but are also found in fatty tissue and muscle tissue. Because they are stored nutrients, there is a risk for toxicity especially through supplementation which is why it is important to work with a practitioner who is familiar with how to properly recommend supplements. When consumed in the diet and supplements correctly, these vitamins work synergistically, meaning they work together to provide the intended benefit. For example, K2 is required for vitamin D to be best absorbed and utilized for bone-building tasks and immune function.

Why are FSV important for fertility and pregnancy?

We’re suffering from an epidemic of nutrient deficiency, and that is, in turn, contributing to a rapid decline in fertility rates. Poor nutrition is also a factor in the rising rates of conditions like gestational diabetes and in pregnancy-related complications.  

Fat-soluble vitamins play an important role in the absorption of minerals and assimilation of protein. In other words, without sufficient fat-soluble vitamins, the process of protein synthesis, which is essential for growth and development, will be inefficient. This is one of many reasons why it is important to maintain adequate levels of fat-soluble vitamins. The adequacy of fat-soluble vitamin levels not only keeps you healthy, it also helps to prevent pre-disposing your child to various chronic diseases.  Each of the fat-soluble vitamins play a specific role in fertility and pregnancy, either directly or downstream effects. 

Vitamin A

• Play an important role in the development of sperm and egg
• Important for maintaining the cell lining of the lungs, protecting us from inhaled pollutants (think environmental toxins) and infectious disease (germs)
• Important for full term pregnancy and prevents prolonged labor 
• Important for fetal development of the face, prevents deafness, and internal organ displacement  
• Important for fetal kidney development; mild deficiency has shown to predispose us to kidney problems later in life

Vitamin D

• Has been shown to help improve blood sugar balance by increasing insulin sensitivity and insulin production 
• Important for proper fetal skeletal development 
• In this study clinical pregnancy rates were lower among vitamin D-deficient recipients than among vitamin D-replete recipients
• Virtually every cell in the body has a vitamin D receptor, which, when bound to vitamin D, can influence the expression of more than 200 genes (1, 2)
• Regulates immune function, cell growth, and neuromuscular function (5, 6).

Vitamin E

• A powerful antioxidant, which can help to reduce inflammation caused by oxidative stress
• Prevents oxidative damage to sperm; if deficiency is present, it can cause poor sperm motility and low sperm count 
• Adequate levels ensures proper cervical mucus production
• Supplementation may aide in the thickening of the endometrium in women with low estrogen

Vitamin K

• While there is no specific RDA for pregnancy yet, Vitamin K is an essential fat soluble vitamin for pregnancy and is found mostly in grass-fed dairy
• K1 is important for blood clotting, while K2 is essential for bone and heart health 
• Important for keeping calcium out of soft tissue, a risk factor for heart disease 
• Important for fetal development of face,skull and nervous system 
• K2 is needed for healthy development of your baby’s face, skull and nervous system
• A deficiency can contribute to underdevelopment of face, jaw, and sinuses, contributing to crooked teeth and poor dental arches
• Binder’s Syndrome where middle 3rd of the face is underdeveloped caused by K2 deficiency

How Can You Get Them In Your Diet?

Fat soluble vitamins are found almost exclusively in animal fats. This is why lean protein consumption can be problematic for fertility. Consumption of protein without sufficient fat present causes our bodies to pull stored fat soluble vitamins from our liver, therefore depleting some of our stored supply. Plant sources of fat-soluble vitamins need a fat source to be absorbed. For example, to get the benefit from the vitamin K from dark leafy greens you could pair it with an olive oil based dressing or some grass-fed cheese. 

Dietary Sources of Fat Soluble-Vitamins

Vitamin A 

• Beef liver
• Cod liver oil
• Orange vegetables also include Vitamin A, however, this is in the beta-carotene form, which has to be converted to active retinol. The conversion rate is only 3% and 45% of the population lack the ability to convert beta-carotene to retinol! 

Vitamin D 

• Herring
• Mackerel
• Salmon
• Sardines
• Cod liver oil
• Grass-fed dairy products especially butter
• The best source of Vitamin D comes from getting your skin exposed to natural sunlight. During the right time of year, you can absorb 10,000-20,000 IU of vitamin D from 15-30 minutes of sun exposure, WITHOUT sunblock. 

Vitamin E

• Nuts
• Berries
• beet greens
• collard greens
• Spinach
• Cabbage
• red bell pepper
• Asparagus
• Mango
• avocado 

Vitamin K 

• K1 sources include kale, spinach, collard greens, and beet greens 
• K1 to K2 conversion is not efficient in humans so K2 is a great go-to

Vitamin K2

• Goose liver
• Hard and soft cheeses
• Grass-fed dairy
• egg yolk  

For done-for-you meals plans that contain all of the fat soluble vitamin requirements you need for optimized fertility, join us in the Fueling Fertility Tribe.

Sources:

1. Vitamins. (2022, January 22). Medline Plus. Retrieved February 6, 2022, from https://medlineplus.gov/ency/article/002399.htm 

2. Kresser, C. K. (22–02-01). The Healthy Baby Code: Fat-Soluble Vitamins: A, D, K, E [Slides]. Https://My.Chriskresser.Com. https://my.chriskresser.com/program/healthy-baby-code/module3/

3. Lemieux, P., Weisnagel, S. J., Caron, A. Z., Julien, A. S., Morisset, A. S., Carreau, A. M., Poirier, J., Tchernof, A., Robitaille, J., Bergeron, J., Marette, A., Vohl, M. C., & Gagnon, C. (2019). Effects of 6-month vitamin D supplementation on insulin sensitivity and secretion: a randomised, placebo-controlled trial. European Journal of Endocrinology, 181(3), 287–299. https://doi.org/10.1530/eje-19-0156

4. Mohd Mutalip, S., Ab-Rahim, S., & Rajikin, M. (2018). Vitamin E as an Antioxidant in Female Reproductive Health. Antioxidants, 7(2), 22. https://doi.org/10.3390/antiox7020022

5. Vitamin E and Fertility Treatments – What to Know to Improve Your Chances of Conceiving. (2019, July 4). Legacy IVF. Retrieved February 6, 2022, from https://legacyivf.com/vitamin-e-and-fertility-treatments-what-to-know-to-improve-your-chances-of-conceiving/

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