Important Nutrients

Dr. Yami is a board-certified pediatrician, certified lifestyle medicine physician, and certified health and wellness coach. As a passionate promoter of healthy lifestyles, “Dr. Yami” champions the power of plant-based diets for the prevention of chronic disease. Read along to learn about the nutrients she finds especially important. The human body cannot produce everything it…


Vitamin D promotes calcium absorption. It is critical for bone growth, immune function, and inflammation reduction. Vitamin D deficiency can lead to rickets in children and osteomalacia in adults. Both of these conditions soften bones, leaving them weak and brittle.


Sources of Vitamin D:

  • Sunlight on bare skin
  • Fatty fish (salmon, trout, cod liver oil)
  • Mushrooms that have been exposed to sunlight
  • Fortified foods (milk, cereal, and orange juice)

Certain factors can prevent us from getting sufficient Vitamin D from sunlight. These include latitude (north of New Mexico, Arizona, and Oklahoma), clothing, sunscreen, shade, windows (UVB cannot go through glass), smog, clouds, the time of day, the season, and your skin’s melanin content.

How much is recommended?

  • 0-12 months: 400 IU (10 mcg)
  • 1-18 years: 600 IU (15 mcg)
  • 19-70 years: 600 IU (15 mcg)
  • >70 years: 800 IU (20 mcg)

**Recommended dietary allowances for adequate intake from the Food and Nutrition Board committee.*

Amount of Vitamin D in plant-based foods:

  • Fortified Plant Milks: 1 cup = 100-144 IU
  • Mushrooms (exposed to UV light): 1/2 cup = 366 IU

Who is at risk for deficiency?

  • Exclusively breastfed babies
  • People with darker skin
  • People taking oral steroids, certain weight loss drugs, cholesterol medication, and certain seizure medications.
  • People with Crohn’s and Celiac
  • People with fish-free diets
  • People who do not eat fortified foods
  • People with increased body fat
  • Older adults

Vitamin D & Sunlight:

Humans produce Vitamin D when they are exposed to UV-B rays from sunlight. However, the sunlight must come in contact with bare skin. Sunlight exposure can produce 10,000-25,000 IU of Vitamin D. You can never get too much Vitamin D from sunshine.

In the spring and summer, 15-20 minutes of sun with bare arms and legs, between the hours of 10am-3pm, can produce the daily dose of Vitamin D. Those with darker skin tones may need to stay outside longer.

Remember that increased sun exposure also comes with the risk for skin cancer. After sunning yourself for 15-30 minutes, make sure to put on sunscreen.

Vitamin D Fortification:

Vitamin D concentrate is added directly to cow’s and plant milk. They are often fortified at comparable levels. Check labels for added Vitamin D. Yogurt, tofu, cereal and orange juice also come in fortified varieties.




Vitamin B12 comes from bacteria, not animals or plants. Many animal products are high in Vitamin B12 because they accumulate the bacteria throughout their lives. With pesticides and antibiotics being used in soil, plants are no longer a reliable source of B12. Thankfully, certain mushrooms and seaweed still contain it. Cereal, plant-based milks, and nutritional yeast are also now fortified with a crystalline version of B12. This crystalline form is actually easier for our bodies to absorb.

Vitamin B12 is crucial for red blood cell formation, DNA synthesis, metabolism, and neurologic function. Vitamin B12 deficiency can lead to weakness, fatigue, appetite loss, neurological symptoms, depression, and memory problems.


Vitamin B-12 Sources:

  • Animal products such as eggs, dairy, and meat
  • Fortified plant foods including nutritional yeast and cereal.
  • Breast milk
  • Infant formula
  • Supplements

Who Is at Risk for Deficiency:

  • Adults over the age of 50 (because the stomach acid required to absorb B12 decreases)
  • People with pernicious anemia
  • People with Celiac or Crohn’s
  • People who have had weight loss or gastric surgery
  • Pregnant and lactating vegan moms
  • Vegans and vegetarians

How Much Is Recommended?

  • 0-6 months: 0.4 mcg
  • 7-12 months: 0.5 mcg
  • 1-3 years: 0.9 mcg
  • 4-8 years: 1.2 mcg
  • 9-13 years: 1.8 mcg
  • 14+ years: 2.4 mcg
  • Pregnancy/lactating: 2.8 mcg


There is no known intake level that is toxic, but high doses may cause acne or rashes.




Calcium is the most abundant mineral in our bodies. Calcium levels in our circulatory system stay the same and do not fluctuate with consumption. When blood calcium levels fall too low, our bones release calcium into the blood. 99% of our calcium is stored in our bones.


Why is it important?

Calcium is required for bone formation, muscle contraction, blood vessel contraction, hormone secretion, and nerve signaling.

Inadequate calcium intake leads to osteoporosis and osteopenia. These cause bone fractures and weak bones.


  • Dairy
  • Green Beans
  • Nuts & Seeds
  • Foods fortified with calcium

Note: Infants receive all the calcium they need from breastmilk or formula

How Much Is Recommended?

Calcium table

Amount in Plant Foods:

  • Fortified Plant Milk (1 cup): 300-450 mg
  • Tofu (½ cup): 200-400 mg
  • Blackstrap Molasses (2 tbsp): 200-400 mg
  • Fortified Orange Juice (1 cup): 350 mg
  • Cooked Broccoli Rabe (1 cup): 200 mg
  • Cooked Soybeans (1 cup): 184 mg
  • Cooked Kale (1 cup): 177 mg
  • Sesame Seeds (2 tbsp): 176 mg
  • Cooked Bok Choy (1 cup): 168 mg
  • Cooked White Beans (1 cup): 161 mg
  • Fortified Breakfast Cereal (1 serving): 130 mg
  • Shelled Edamame (1 cup): 122 mg
  • Almond Butter (2 tbsp): 111 mg
  • Chia Seeds (1 tbsp): 76 mg

What About Supplements?

It is not recommended to take calcium supplements. There are risks associated with excess calcium intake, including kidney stones, constipation, cardiovascular disease, interactions with medications, and decreased iron and zinc absorption.

The best way to add calcium to your diet is through natural and fortified foods.

Absorption Varies:

  • Average calcium absorption from food is about 30%.
  • In infants & young children, absorption can be as high as 60%.
  • In older adults, absorption can drop to 15-25%
  • High sodium consumption leads to increased calcium excretion.
  • High caffeine intake can lead to decreased absorption and increased excretion.

How Much per Day?

Despite popular belief, a diet high in calcium is not necessary to protect against bone fractures. Some experts believe that we don’t need as much as the Institute of Medicine suggests. Overall diet and lifestyle can impact calcium and bone metabolism. Cultural, genetic, and geographic differences also play a role.




Bone health isn’t only about calcium. Bones are dynamic, and are constantly remodeled throughout our lives. In children and teenagers, bone formation exceeds breakdown, but for adults it can be the other way around.


Risk Factors for Osteoporosis:

  • Age (typically affects older adults)
  • Female (lower estrogen post-menopause)
  • Low body weight
  • Ethnic background (increased in white and asian populations)
  • Inactivity/sedentary lifestyle
  • Disordered/restrictive eating practices
  • Smoking
  • Family history
  • Long-term use of certain medications such as steroids
  • Certain medical conditions that affect nutrient absorption

What to Avoid:

  • High sodium diet
  • Smoking
  • Excess Alcohol
  • Excess Caffeine

What to Include:

  • Exercise such as walking, running, climbing, and resistance training.
  • Adequate Calcium intake
  • Adequate Vitamin D intake
  • Adequate protein intake
  • Adequate intake of Magnesium, Manganese, Vitamin K, folate, Vitamin C, Potassium, and Boron
  • Lots of fruits and veggies!



Iron deficiency is the most common nutritional deficiency in the world. Iron is a major component of hemoglobin, a type of protein in red blood cells that carries oxygen through the body. It is also necessary for growth, neurologic development, cellular functioning, muscle metabolism, and the synthesis of some hormones.

There are two types of iron, heme – derived from animal products, and non-heme – derived from plants.


Where Do You Get It?

You can find iron in animal, plant, and fortified foods. Vegans can easily obtain sufficient iron from plant-based foods.

Iron per Serving:

  • Fortified Breakfast Cereal: 18mg
  • 1 Cup White Beans: 8mg
  • Dark chocolate (45-69%): 7mg
  • ½ Cup Lentils: 3mg
  • ½ Cup Spinach: 3mg
  • ½ Cup Firm Tofu: 3mg
  • ½ Cup Kidney Beans: 2mg
  • ½ Cup Chickpeas: 2mg
  • ½ Cup Sardines: 2mg
  • 3 oz. Beef: 2mg
  • 1 Baked Potato: 2mg
  • 1 oz. Cashews: 2mg
  • ½ Cup Green peas: 1mg
  • 3oz. Chicken: 1mg
  • ½ Cup Broccoli: 1mg
  • 1 Hard Boiled Egg: 1mg
  • 1 Slice White or Wheat Bread: 1mg

How to Improve Iron Absorption:

  • Phytates, polyphenols and calcium can inhibit iron absorption
  • Avoid taking calcium supplements at meals
  • Add a source of Vitamin C to meals (bell peppers, citrus, tomato)
  • Avoid coffee and tea at meals (polyphenols)
  • Eat more legumes (lentils, peas and beans)
  • Soak or sprout beans and whole grains prior to cooking

How Much Is Recommended?


Who Is at Risk for Iron Inadequacy?

  • Menstruating women
  • Pregnant women
  • Premature, preterm, and low birthweight babies
  • Exclusively breastfed babies between 4-6 months of age
  • Frequent blood donors
  • People with malabsorption from chronic conditions or surgery
  • Children consuming excess cow’s milk and dairy

Be careful!: Accidental ingestion of iron supplements can be toxic! Always keep out of reach of children




Iodine is an element naturally found in earth’s soil and seas. It is usually in the form of salt. Iodine is necessary for proper thyroid, metabolism, and immune system function.


Iodine Deficiency

  • The earliest sign of deficiency is a goiter (enlarged thyroid gland)
  • In pregnancy, deficiency can lead to the baby being born with impaired neurological function, stunted growth, and physical deformities.
  • Iodine deficiency is the most common cause of preventable intellectual disability in the world

Sources of Iodine

  • Found in seaweed (nori, kombu, kelp, wakame)
  • Breastmilk and infant formula
  • Fish and seafood
  • Table salt fortified with Iodine
  • Fortified enriched bread
  • Chicken eggs
  • Cow’s milk

Note: specialty salts and salt in processed packaged foods are not typically iodized

How Much Is Recommended Daily?

  • 0-6 months: 110mcg
  • 7-12 months: 130mcg
  • 1-8 years: 90mcg
  • 9-13 years: 120 mcg
  • 14+ years: 150mcg
  • Pregnancy: 220-250mcg
  • Lactation: 290mcg

**IOM Food and Nutrition Board
**WHO, UNICEF and ICCIDD recommend 250 mcg per day for pregnant women*

Iodine Food Sources:

  • 10g Dried Seaweed: 232mcg
  • 3 oz. Baked Cod: 158mcg
  • ¼ tsp Iodized Salt: 76mcg
  • 3 oz. Cooked Shrimp: 13mcg

Absorption Barriers:

  • Levels in soil vary and may lead to insufficient intake in some regions
  • Goitrogens are substances that inhibit iodine uptake in the thyroid
  • Soy, cassava, sweet potato, millet, and cruciferous vegetables are goitrogens
  • Selenium, vitamin A, and iron deficiency can inhibit iodine uptake as well

Who Is at Risk for Deficiency?

  • People who don’t eat iodized table salt
  • Pregnant women
  • Vegans (especially if they don’t eat salt or seaweed)
  • Residents of areas with iodine-deficient soil.

Should You Supplement?

If you do not eat iodized salt, seaweed, or seafood, then it is okay to supplement. The YUMI multivitamin contains a safe amount of iodine. Iodine only supplements and kelp supplements can contain amounts that are too high and should be avoided.




Omega-3s are polyunsaturated fatty acids. One type of Omega-3s is alpha-linolenic acid (ALA), which cannot be made by the human body.


Why Do We Need It?

Omega-3s support the cardiovascular, pulmonary, immune, and endocrine systems. They also provide energy and have anti-inflammatory properties.

Deficiency can cause rashes and dry skin.

Omega-3 Sources

  • ALA is found in flax seeds, chia seeds, hemp seeds, walnuts, and flax, canola and soybean oil
  • DHA and EPA are found in fish, seafood, and seaweed

How Much Is Recommended Daily?


ALA Sources:

  • 1 tbsp Flaxseed Oil: 7,260mg
  • 1 tbsp Chia Seeds: 2,139mg
  • 1 oz. English Walnuts: 2,570mg
  • 1 tbsp Ground Flaxseeds: 1,710mg
  • 1.5 tsp Soy Oil: 450mg
  • 1 tsp Canola Oil: 433mg
  • ½ cup Soybeans: 500mg
  • 1 cup Firm Tofu: 400mg
  • 1 cup Tempeh: 400mg

Supplements for Vegans:

  • Try to obtain adequate ALA from chia seeds, flaxseeds, and walnuts
  • Vegan DHA/EPA supplements are made from microalgae. 150-300mg supplements are a good choice.
  • Algal oil supplements
  • The American Academy of Pediatrics recommends that pregnant and breast breastfeeding women consume 200-300 mg of DHA per day



If a food is “fortified” that means that vitamins and/or minerals have been added to it. Food fortification began in the 1920’s to combat common nutritional deficiencies.


Nutrients Added to Fortified Foods in the United States

  • 1924 – Iodine – Salt (to prevent goiter)
  • 1933 – Vitamin D – Milk (to prevent rickets)
  • 1940 – Thiamin, Niacin, Riboflavin, Iron – Wheat Flour
  • 1945 – Fluoride – Water supply (to decrease cavities)
  • 1988 – Folic Acid – Wheat flour, enriched cereal grain products, other products (to prevent neural tube defects in babies)

Please consult with YOUR medical provider to determine if supplementation is appropriate for you or your child.

About the Author

Dr. Yami Cazorla-Lancaster

Pediatrician & Health Coach

More posts from Yami.


  • Calcium Vitamins and Minerals
  • Harvard T.H. Chan School of Public Health. The Nutrition Source. Vitamin D.
  • How much calcium do you really need? Harvard Health Publishing, Harvard Medical School
  • National Institutes of Health Calcium Fact Sheet for Professionals
  • National Institutes of Health. Office of Dietary Supplements. Vitamin D Fact Sheet for Consumers.
  • National Institutes of Health. Office of Dietary Supplements. Vitamin D Fact Sheet for Health Professionals.
  • National Institutes of Health: Iodine Fact Sheet for Professionals
  • National Institutes of Health: Iron Fact Sheet for Professionals
  • National Institutes of Health: Omega-3 Fatty Acids Fact Sheet for Professionals
  • National Institutes of Health: Vitamin B12 Fact Sheet for Professionals
  • The Vegetarian Resource Group: Calcium in the Vegan Diet
  • WHO: Nutrition: micronutrient deficiencies
  • World Health Organization: Recommendations for Preventing Osteoporosis