Essential Nutrients for Women Practicing Intermittent Fasting

Intermittent fasting can be a practical weight-loss technique with a number of potential benefits for health, however, there are some key considerations that fasters should make – one of them being sufficient nourishment.

Women naturally have higher requirements for certain vitamins in minerals than men do, simply due to gender-specific bodily functions. These nutrients deserve special attention, particularly during periods of food restriction, such as intermittent fasting.  So, let’s delve into some of the most important nutritional considerations for women practicing IF!

Folate (Vitamin B9)

Folate (Vitamin B9) plays a key role in many processes in the body, including DNA and RNA synthesis, and the development of the fetus in pregnant women. This is extremely important as Folate deficiencies can lead to serious spinal and brain birth defects. 

With a daily requirement of 400mcg per day, women of child-bearing age are often recommended to increase their intake of folate-containing foods such as grains, seeds, spinach, asparagus, broccoli, lettuce, beans, fish and eggs; and to take Folic Acid supplements. Folic Acid is also often added to a range of off-the-shelf products such as bread, pasta and rice [1].   

Adding extra greens or seeds to your main meals (i.e. spinach to your pasta, or sunflower seeds to your salad) can help increase your folate intake during fasting.

Iodine

Iodine intake from food is also essential for women, which is necessary for the normal functioning of the thyroid[2]

One of the reasons for this is that thyroid disorders such as hypothyroidism and hyperthyroidism are more common in women, compared to men, with the risk increasing with age. In addition, there are some studies indicating that fasting can impact hormone balance of the thyroid system, reducing levels of T3 – a hormone produced by the thyroid[3,4].

Include sources of Iodine such as eggs and seafood in your diet regularly to assist normal thyroid hormone production and thyroid function[5]

Iron

Women have higher requirements for Iron due to regular body functions such as menstrual cycle. In fact, an estimated 50% of women with heavy menstrual bleeding are affected by iron-deficiency anemia[6]. Iron comes from food in two main sources: animal (heam) and plant (non-heam iron). Sources include meat and subproducts, as well as spinach, beans and fortified cereals[6]

Plant (non-heam) iron is more poorly absorbed by the body, however, combining it with food sources of Vitamin C, such as tomatoes, bell peppers, strawberries and citrus fruit can help increase absorption. 

Copper and Selenium

Some trace elements such as Copper and Selenium, although required in very small quantities, are commonly deficient in women[7].

Copper is an essential component of enzyme and an antioxidant, which is also associated with iron levels and anemia. Sources include seafood, seeds and nuts, chickpeas and wholegrains[8].

On the other hand, Selenium is an antioxidant, insufficient intake of which is linked to chronic disease and infertility. It is contained within dairy, meat, fish, eggs, nuts, seeds, beans and lentils[9]

References:

[1] Harvard The Nutrition Source – Folate (Folic Acid) – Vitamin B9. Link

[2] Mulder, JE. THYROID DISEASE IN WOMEN. Medical Clinics of North America 82(1) January 1998, pp: 103-125. Link

[3] Kim, BO, Joo, Y, Kim, MS, Choe, HK, Tong, Q, Kwon, O. Effects of Intermittent Fasting on the Circulating Levels and Circadian Rhythms of Hormones. Endocrinology and Metabolism 2021 Aug; 36(4) pp: 745–756. Link

[4] Fontana, L, Klein, S, Holloszy, JO, Premachandra, BN. Effect of Long-Term Calorie Restriction with Adequate Protein and Micronutrients on Thyroid Hormones. The Journal of Clinical Endocrinology & Metabolism August 2006 91(8) pp: 3232–3235. Link

[5] National Institute of Health. Iodine

Fact Sheet for Health Professionals. Updated: April 2022.  Link

[6] Office on Women’s Health. Iron-deficiency anemia. Updated: February 2021. Link

[7] Fayet-Moore, F, Petocz, P, Samman, S. Micronutrient Status in Female University Students: Iron, Zinc, Copper, Selenium, Vitamin B12 and Folate. Nutrients. 2014 Nov; 6(11): pp: 5103–5116. Link

[8] National Institute of Health. Copper Fact Sheet for Health Professionals. Updated: March 2021. Link

[9] National Institute of Health. Selenium Fact Sheet for Health Professionals. Updated: March 2021. Link