4 lesser known nutrients that a woman’s body needs
written by Kirstin Kade from Taste & See
As women, we are aware that our needs often differ from our male counterparts. Central to these needs is our unique hormonal and metabolic makeup, our monthly menstrual cycle, and our ability to fall pregnant, nourish a growing foetus, and give birth. We also know that it is important to consume a diverse range of different nutrient-rich foods in our diet to provide our bodies with the macronutrients we require for energy, but all too often we overlook our need for many key micronutrients.
These are nutrients that we require in larger daily amounts (tens or hundreds of grams) to provide energy and support normal growth, health, and maintenance in our bodies. Carbohydrates, proteins, and fats are included in this group of nutrients.
These are nutrients that we require in very small quantities in our diet (several milligrams or micrograms per day), but are critically important to the proper functioning of our brain, bones, and body. Vitamins and minerals are included in this group of nutrients.
A group of unique organic compounds that are required for normal growth, health, and metabolic integrity of our bodies. They are essential in our diet, as our bodies are unable to synthesise them.
In contrast to vitamins, minerals are essential inorganic elements that have an important physiological function in the body. They are required in the diet in either macro (milligram) or trace (microgram) amounts.
Recommended Nutrient Intake (RNI)
– This is the amount of a nutrient that should be enough to ensure that the needs of nearly all of the population (97.5%) are being met.
1 — Folic acid / Folate
Folate and folic acid both refer to a B vitamin that is critical for red blood cell production, DNA formation during cell replication, and nerve function. Folate is the form found naturally in food, whilst folic acid is the form that is commonly found in supplements and fortified foods.
Folate is important in the first trimester of pregnancy, which is often the time when a woman doesn’t even know that she is pregnant. It is during these first few weeks that a foetus experiences rapid spinal cord and nerve cell development, and when a pregnant mother has insufficient folate status, the DNA synthesis and cell replication in a growing foetus can be affected and result in severe birth defects such as neural tube defects.
Women of childbearing should consume sufficient folate-rich foods to meet the RNI of 200µg/day. Women who are considering pregnancy or are pregnant should take a 400µg folic acid supplement (after consulting a healthcare professional) in addition to consuming folate-rich foods.
Good dietary sources of folate include:
· Green leafy & cruciferous vegetables (spinach, kale, Brussels sprouts, cabbage, and broccoli)
· Beans & legumes
· Wheat bran & whole grains
· Meat, fish & poultry
· Folate-fortified foods
Although folate is widely found in food it is often lost through cooking, so a good way to preserve the folate found in your vegetables is to lightly steam them where possible or consume them raw.
2 — Iron
Iron is essential for the production of haemoglobin and healthy red blood cells, which are needed to carry oxygen throughout our body. Iron deficiency is one of the most common nutritional deficiencies worldwide, and is particularly prevalent in women due to the monthly iron losses we experience through menstruation. Iron deficiency can lead to exhaustion, fatigue, dizziness, an irregular heartbeat, shortness of breath, and weakness due to the fact that less oxygen is able to reach the tissues where it is needed for energy production and cell metabolism. Iron also has an important role to play in maintaining a healthy immune system, so mild iron deficiency can often result in a higher susceptibility to infections.
Our bodies are amazing, so although iron needs increase during pregnancy, the combination of no menstruation and increased efficiency of iron absorption mean that a pregnant mother with optimal iron stores does not usually need to increase her iron intake during pregnancy.
Iron is found in either the haem or non-haem form in foods. Haem iron is present in animal sources such as red meat, poultry and eggs, and is very well absorbed by the body. Non-haem iron can be found in plant foods such as legumes, dark green leafy vegetables, tofu, nuts, seeds, and fortified cereals.
Although non-haem iron is not absorbed as well as haem iron, vegetarians and vegans should be able to meet their daily needs by consuming a variety of iron-rich plant foods in their diet including chickpeas, kidney beans, dried apricots, Brazil nuts, hazelnuts, sesame seeds, tofu, and spinach. A top tip for optimising iron absorption is to consume vitamin C rich foods alongside iron-rich plant foods, because vitamin C helps to enhance iron absorption in the gut.
3 — Vitamin D
Vitamin D has several important functions in the body, including the:
· Promotion of calcium absorption
· Regulation of calcium and phosphate levels in the blood
· Promotion of bone health and cell growth
· Reduction in systemic inflammation
It’s also becoming more evident that this vitamin has an important role to play in women’s health, particularly in the activity of reproductive hormones such as oestrogen.
Before we get started, it’s important to know that vitamin D is the only vitamin that our bodies are able to produce. When UVB rays of a specific wavelength hit our skin, vitamin D3 is produced from a steroid prohormone known as 7-dehydrocholesterol. This is why individuals that live far North or South are at risk of developing vitamin D deficiency and a daily 10µg vitamin D supplement is recommended during the Autumn and Winter months when UVB exposure is low.
Although the majority of our vitamin D is produced by our body, we can also benefit from obtaining small amounts of it in our diet. There are two major dietary forms of vitamin D, namely cholecalciferol (D3) and ergocalciferol (D2).
These are commonly found in
· Oily fish
· Egg yolks
· Fortified dairy, cereals and soy products
· Mushrooms grown in the sun
Most of us know that vitamin D is important for good bone health in women, however new research has also highlighted its importance in immune function, cell metabolism, as well as good pregnancy outcomes. Optimal vitamin D status is important in pregnancy because a developing foetus obtains all of the vitamin D that it needs for bone and immune system development from its mother. Babies that are born with low levels of vitamin D and infants that don’t obtain enough through breast milk or formula may develop rickets, which can cause permanent bone deformities and growth retardation. Poor vitamin D status in women increases their risk of developing osteomalacia (bone softening) and osteoporosis later in life.
4 — Iodine
Probably the least well known of these four micronutrients, iodine is an essential component of our thyroid hormones T4 (thyroxine) and T3 (tri-iodothyronine). These hormones are critical for the regulation of our metabolism, breathing, heart rate, growth, temperature, and even digestion. When our iodine requirements are not met through dietary intake, our thyroid is unable to produce sufficient amounts of these hormones and we can end up experiencing exhaustion, an inability to concentrate, unexplained weight gain, and feeling really cold (even on hot days).
A pregnant mother’s thyroid hormones also have a direct effect on the brain development of a growing foetus, and ensuring adequate iodine status in women before and during pregnancy is one of the most important preventable cause of irreversible brain damage in infants. Although up to 20mg of iodine can be stored in our thyroid, we still require a daily intake through our diet. The WHO RNI for iodine is 150µg/day for adult women and 250µg/day for pregnant and lactating women.
Iodine is naturally found in our soils and seawater, so some of the best dietary sources of iodine include:
The availability of iodine in foods differs between regions. Those living in countries such as South Africa and the United States can easily maintain adequate iodine intake through the consumption of iodised salt. In the U.K. on the other hand, the main dietary source of iodine is cow’s milk and dairy products due to the iodine-rich cattle feed.
Most women following a healthy, balanced diet containing these foods should be able to meet their iodine needs with ease, and taking an iodine supplement without medical supervision is not recommended because excessive iodine intake can result in thyroid problems.
Kirstin is a qualified Food Scientist and is currently studying a MSc Human Nutrition at the University of Surrey in the U.K. Her blog, Taste & See, is a space where she shares nutrition-related knowledge and wholesome recipes that aim to make good health through food accessible to others.
1 — Introduction to Human Nutrition (Gibney et al.)
2 — Bernal, J. Thyroid hormones and brain development. Vitam Horm. 2005;71:95-122.
3 — Kapil U. Health Consequences of Iodine Deficiency. Sultan Qaboos Univ Med J. 2007 Dec;7(3):267-72.
4 — Khadilkar SS. The Emerging Role of Vitamin D3 in Women’s Health. J Obstet Gynaecol India. 2013 Jun;63(3):147-50.
5 — American Thyroid Association – Iodine Deficiency
6 — Willing MC, Sowers M, Aron D, Clark MK, Burns T, Bunten C, Crutchfield M, D’Agostino D, Jannausch M. Bone Mineral Density and Its Change in White Women: Estrogen and Vitamin D Receptor Genotypes and Their Interaction. J Bone Miner Res. 1998;13:695-705.
1 — Folate – https://www.bda.uk.com/foodfacts/FolicAcid.pdf
3 — Vitamin D – https://www.bda.uk.com/foodfacts/VitaminD.pdf
4 — Iodine – https://www.bda.uk.com/foodfacts/Iodine.pdf