5 Key Nutrients That Women Need Most
by Janelle Zakour RD
In honour of International Women’s Day, (which is today!! March 8th every year!!), we will be discussing women-specific nutrition. As children, the nutritional needs of both boys and girls are fairly similar but once puberty strikes, women begin to develop unique nutritional requirements. As women age and as their bodies change both physically and hormonally, their nutritional needs also evolve, making it crucial that their diet meets these needs. Women generally require fewer calories than men, however, due to hormonal changes associated with menstruation, childbearing and menopause, their requirements for certain vitamins and minerals are much higher as women are at a higher risk for weakened bones, osteoporosis and anaemia. (There may also be a connection between anaemia and osteoporosis. Read here.)
Here are 5 key nutrients that women need most.
1. Folate & Folic Acid (Vitamin B9)
These two terms are used interchangeably however there is a difference. Folate is found naturally in foods whereas folic acid is its synthetic form found in fortified foods and supplements. It is one of the most underappreciated micronutrients as it helps the body perform many essential functions including red blood cell creation, production of genetic material (DNA and RNA) and many others.
However it is obtained, this is an absolutely crucial nutrient for all women of childbearing age where the Recommended Daily Allowance (RDA) is 400 mcg of the vitamin. This number increases to up to 600 mcg daily during pregnancy. Folate and folic acid reduces the risk of neural tube defects, which are birth defects of the brain, spine or spinal cord as well as prevent other pregnancy-related complications. The two most common neural tube defects are spina bifida and anencephaly and these can be avoided by a sound folic acid intake before and during pregnancy. A lack of folate can trigger anaemia and has been linked to an increased risk of developing cancers of the cervix, colon, brain and lungs.
Good dietary sources of folate include dark leafy greens, okra, cruciferous veggies (broccoli, cauliflower), avocado, legumes (lentils, black-eyed peas, sunflower and flax seeds, peanuts and almonds), paw paw, citrus (oranges), beets, liver, fermented dairy (yogurt, kefir). If you fall short on your food intake, supplementation can be an option.
Iron helps to create the hemoglobin that carries oxygen in the blood. Some iron is also required for enzyme activities in the body. Too little iron as well as too much, can be damaging therefore it is important to find a balance. Women who are of childbearing age, who are pregnant and who are adolescent and have begun menstruating are most at risk for developing iron deficiencies and require almost twice the amount of iron that men do. The RDA for iron in women between the ages of 19 and 50 is 18 mg. Pregnant women will need more than this at 27 mg and post-menopausal women over 51 will need less at around 8 mg. Dietary iron has two main forms: heme and nonheme. Heme foods tend to be animal-based and include red meat, liver, chicken, turkey and oysters. This type of iron is twice to three times more easily absorbed by the body and is a large source of dietary iron. Nonheme iron is largely plant-based and is less readily absorbed than heme iron. It is found in legumes (lentils, kidney beans), soy foods (tofu, tempeh), dark leafy greens, dried fruit (apricots, raisins), nuts (cashews, almonds), seeds (pumpkin, sunflower), blackstrap molasses, cereals and fortified foods. It is also found in some animal foods such as dairy and eggs. Vegetarian women need 1.8 times as much iron to make up for the low bioavailability in nonheme iron foods. A deficiency in iron can cause iron-deficiency anaemia to develop, a condition in which blood lacks adequate healthy red blood cells and experience symptoms such as fatigue, weakness and pale skin. To combat this, combine nonheme food sources with Vitamin C as this increases iron absorption. Examples include eggs for breakfast with ½ an orange on the side, tuna salad with bell peppers and tomatoes or a bean salad with lemon juice.
99% of the calcium in our body is found in our bones and teeth where it plays two roles; 1. it forms the rigid structure of our body which keeps us upright and 2. acts a calcium bank offering a ready source of the mineral should our blood calcium levels drop. Blood calcium participates in muscle contraction, blood clotting and nerve impulses and is regulated by Vitamin D and other hormones. The RDA for calcium in adult females between the ages of 19 and 50 is set at 1000 mg provided that enough calcium was obtained during the growth years to provide a strong and dense bone structure. However, bone mineral density decreases as we age. Certain hormones such as estrogen help the body build healthy bones and this is why post-menopausal women have higher requirements of calcium when estrogen levels drop, climbing up to as much as 1500 mg per day. Even when calcium intake is low, blood calcium remains normal, at the expense of bone loss, which can lead to osteoporosis, primarily in women. In addition to diet, exercise and other lifestyle factors can also play an important role in maintaining bone health. Weight-bearing exercise and resistance training (dancing, yoga, weight-lifting) can lower your risk of developing osteoporosis. On the other hand, smoking and an excessive alcohol intake increases the risk.
Well-absorbed dietary sources of calcium include sardines, yogurt, milk, tofu, cheddar cheese, broccoli, watercress, mustard greens, kale, pakchoi and even fortified orange juice. Make sure to get lots of sunlight to synthesize Vitamin D which also plays a role in bone health!
4. Omega-3 Essential Fatty Acids
Omega-3 fatty acids are a family of polyunsaturated fats that have all sorts of powerful health benefits for the body, the eyes and the brain. They are considered essential because they are not produced by the body and must be obtained through diet. There are 3 main types of omega-3s: EPA (eicosapentaenoic acid – found in fatty fish, seafood and fish oil), DHA (docosahexenoic acid – found in breast milk, fatty fish and fish oil) and ALA (alpha-linolenic acid – found in high-fat plant foods like flax seeds, chia seeds and walnuts). In adult women, omega-3s can reduce chronic inflammation, which can contribute to heart disease, metabolic syndrome, some cancers and other diseases. Studies have indicated that it can also improve bone strength by increasing the amount of calcium in bones thus reducing the risk of osteoporosis. It also helps in arthritis too. And great news for those suffering with menstrual cramps; an omega-3 supplement was shown to be more effective than ibuprofen in treating severe menstrual pain! In pregnancy, omega-3s are important nutrients to promote foetal brain growth and development as deficiencies are linked to low intelligence, poor eyesight and an increased risk of several health problems. Omega-3s also play a role in adult brain health and can stave off age-related mental decline, can fight depression and anxiety (especially EPA) and can prevent vision impairment and blindness (especially DHA). It can most likely help you get to sleep easier too as low DHA levels have been linked to lower melatonin levels. Finally, it is great for your skin by keeping skin cells healthy, preventing premature again and protecting the skin from sun damage. There is no specific recommended daily intake for omega-3 fatty acids, however the World Health Organization recommends a daily intake of 250 – 500 mg.
The best way to ensure an optimal omega-3 intake is to eat fatty fish (sardines, tuna, mackerel, salmon, herring, anchovies) twice a week and include nuts and seeds as part of a balanced diet. Pregnant and breastfeeding women may need an additional 200 mg. Consider a fish oil, krill oil or seaweed/algae DHA supplement if this isn’t an option. Vegan/vegetarian individuals are often deficient in DHA and should consider supplementing.
5. Dietary Fibre
Dietary fibre encompasses all parts of plant matter that cannot by digested or absorbed in the small intestine. Unlike proteins, fats and carbohydrates, fibre moves through the digestive tract amazingly intact. But they have an incredibly important role to play. There are 2 types of fibre, ‘soluble’ and ‘insoluble’. Insoluble fibre is made up primarily of cellulose and found in foods such as whole grains, nuts and seeds and most vegetables. It assists the general movement of food through the digestive tracts, preventing toxic build-up. Soluble fibre includes pectins and beta glucans and works a bit differently than insoluble fibre. It dissolves in water to form a gel-like substance that helps to balance blood glucose levels and lowers blood cholesterol. It is found in oats, barley, apples, carrots, citrus, chia seeds, psyllium and legumes. Nearly all high-fibre foods contain varying amounts of both soluble and insoluble dietary fibre. Together they form total fibre. Think of this combo as the broom for our intestines. It provides the bulk for our stools, makes them softer and easier to pass and promotes regular bowel movements, thus preventing constipation. Individuals who consume a high-fibre diet achieve a lower body mass and are less at a risk for developing obesity and there are multiple reasons for this. High-fibre foods tend to be more filling so you eat less. Secondly, the more fibre that is in a meal, the lower the glycaemic index of the meal will be as the fibre slows the release of glucose into the bloodstream, keeping you satiated for longer. Finally, high-fibre foods tend to be lower in calories when compared to more refined foods of similar portion sizes. The regular bowel movements will also keep the tummy area less bloated.
If you’re not eating a nutritionally balanced diet, chances are you’re not getting enough fibre as some of the healthiest foods have the highest fibre levels: fruits, vegetables, whole grains, sweet potatoes, whole cereals, nuts, seeds, avocado and legumes. A high-fibre diet is also linked to colon cancer prevention, prevention and maintenance of type 2 diabetes and the prevention of heart disease, hemorrhoids and diverticulosis. The recommended daily intake for women is 25 grams. However, there is such a thing as consuming too much fibre especially if you increase your intake too quickly. The best strategy is to slowly integrate them into your diet, while engaging in light physical activity and drinking lots of water (as fibre absorbs a lot of water as it moves along the gut).
Have a joyous International Women's Week!!
(This article was featured on Propa Eats in the Guardian Newspaper on 07/03/18. You can read it here!)
Recommended Daily Allowance (RDA) figures obtained from the Krause aka 'The Dietitian's Bible'.
Mahan, L. Kathleen., Escott-Stump, Sylvia., Raymond, Janice L.Krause, Marie V., eds. Krause's Food & The Nutrition Care Process. St. Louis, Mo. : Elsevier/Saunders, 2012. Print