Most of the world does not eat a well-balanced diet. In fact, the Global Nutrition Report has found that 1 in 3 people globally is malnourished. For the developing world, this unfortunately is the result of deeper, systemic issues including poverty and food scarcity.
But even in the developed world, our diets are routinely deficient in one or more micronutrients, which can lead to a variety of chronic and acute health problems.
But some of us are at a greater risk than others. Here are 5 groups particularly at risk of developing a clinical micronutrient deficiency.
1. Vegetarians (especially vegans)
You’d be hard pressed to find a doctor, nutritionist, or dietitian who doesn’t promulgate the credo of more fruits and vegetables. But despite the etymology, vegetarians can retain their title in earnest eating nothing but wine, cheese, bread, and chocolate (i.e., low in vegetables).
While many abstain from meat for ethical or environmental concerns, as much as 82% of vegetarians say they choose this dietary lifestyle for reasons of health.
But what if you do eat plenty of fruits and vegetables? Vitamin B12 is the only vitamin derived solely from animal products. This unsurprisingly puts vegans, who eliminate all animal products including eggs and dairy, at an even higher risk. A review of 40 manuscripts found deficiencies ranging to as high as 45% among infants, 33% in young children, and up to 86.5% in adults and the elderly.
Vitamin B12 helps in the formation of red blood cells. It also helps with brain function through the repair of myelin sheaths. Chronic deficiencies in B12 manifest in a lack of energy and a lack of mental clarity.
Fortunately, the USDA and CDC recognized B12’s importance, which has led to B12-fortification into products like cereal. So the good news is that vegetarians, and even vegans, can maintain their lifestyle while maintaining proper nutritional levels. But they may need to be more vigilant. Encouragingly, studies showed that deficiencies were absent in vegetarians who consumed regular quantities of B12-fortified foods.
Bottom line: (1) It’s hard to overdo it on fruits and vegetables, and (2) make sure to consume fortified foods or supplements for vitamin B12.
2. Prenatal
To say that pregnancy puts a strain on the body is an understatement. Eating for two while experiencing hormonal and metabolic changes that can alter nutritional needs and can affect fetal development.
Deficiencies in vitamin B9 (folate) and vitamin B12 are associated with preterm labor, intrauterine growth retardation, low birth weight, and neural tube defects. Pregnant vegetarians were deficient in vitamin B12 by 33% in the first trimester, 17% in the second, and 39% in the third.
And iodine, and inorganic mineral, is critical for fetal development. The nutritional demand for iodine in pregnant mothers increases by 50% due to hormonal changes in the thyroid, and is critical for fetal brain development. In fact, the irreversible fetal brain damage caused by maternal iodine deficiency is the leading cause of preventable mental retardation in the world.
In addition to proper fetal development, changes to nutritional demands are critical for the health of the mother too. Calcium supplementation is recommended to reduce the risk of preeclampsia.
Bottom line: Take your doctor's recommendations about nutrition seriously during pregnancy. And mind the high-flyers like vitamin B9 (folate), iodine, and calcium. In addition to the notion that a well-balanced diet is essential to include adequate levels of all nutrients, there is also suggestive research for supplementing with vitamin B12 and vitamin D.
3. The Elderly
The science of aging is field unto itself. Among the myriad concerns to monitor as you age is your ability to metabolize certain vitamins.
The risk of developing cataracts and macular dystrophy (AMD) increase with age, but may also increase with subclinical intake of some key nutrients found in the eye lens and retina. Several studies suggest that increased intake of vitamin C, vitamin E, zinc, Omega-3 fatty acids, lutein, β-carotene, and zeaxanthin could help reduce the risk of both cataracts and AMD.
Oral health can decline too. The trouble here, is that tooth loss can make healthy foods more difficult to consume, thus leading to more deficiencies and worse health outcomes. Here, studies suggest vitamin D, calcium, and vitamin C are important for keeping your teeth.
Cognitive decline is another risk of aging, and several key nutrients, particularly B vitamins like, B6, B12, and folate, have been correlated to the development of dementia at subclinical levels. Vitamin B12 shows up again as a deficiency among the elderly, primarily due to changes in the ability to break it down and absorb it.
Bottom line: A focus on nutrition is important as you age, as diets and age-related metabolic changes increase the prevalence of nutritional deficiencies. Nutrition has a large role to play in improving overall well-being for the elderly, and they should focus on consuming enough protein, n-3 fatty acids, fiber, vitamins B6, B12 folate, D, E, carotenoids (precursor to vitamin A), calcium, magnesium, and potassium.
4. Post-Op
Malnutrition has been shown to be present in 20-50% of hospitalized patients. Deficiencies in key nutrients like vitamin D, zinc, iron, and vitamin C can have a detrimental effect on wound healing and infections through a depressed immune response.
Other surgeries that affect the stomach or digestive tract also impact nutrient absorption and can cause acute malnutrition. Bariatric surgery is a big one. Several studies have shown that the risk of deficiencies of several vitamins and minerals occur after bariatric surgery.
Bottom line: nutrition should be a component to your surgical plan. Malnutrition, even at subclinical levels, can potentially impair your health and delay healing. The key nutrients to be mindful of are very personalized and surgery-dependent.
5. The Obese
What counts as fat is a tricky discussion that depends on your measurement technique. The goal, generally, is to determine your risk for chronic diseases like cardiovascular disease, diabetes, and some cancers.
Obesity comes with many of these health risks. But I bet nutritional deficiencies weren’t the first thing you thought of.
Around 40% of the adult US population had inadequate intake levels of vitamins A, C, D, E, calcium, and magnesium. But as it turns out, overweight and obese Americans had 5 – 12% lower intake of those same micronutrients. As America has a population with over 70% of its citizens overweight or obese, nutritional deficiencies are clearly not just a problem for the developing world.
It turns out, that most citizens on a “western diet” are at risk of developing nutritional deficiencies. While several key micronutrients like vitamin D may be deficient in over 40% of all Americans, subclinical levels low enough to increase the risk of long-term complications are believed to be widespread for other micronutrients like vitamin E, vitamin B12, and calcium.
In fact, our diets are arguably quite a bit out of alignment with optimal health. A study in the Journal of the American Medical Association found the single greatest risk to disease in America was your diet. Most of the leading causes of deaths, in fact, include nutrition as a risk factor:
Heart Disease
Chronic Lower Respiratory Disease
Cerebrovascular Disease (Stroke, and others)
Alzheimer’s Disease
Diabetes Mellitus
Several Cancers
The Big Picture
It’s a good idea to regularly check to ensure your diet is in line with currently recognized levels for optimal nutritional health. Your body has the ability to persevere through temporary deficiencies, and certain fat soluble micronutrients can be stored for long periods of time.
But chronic deficiencies can lead to serious problems if left unchecked. And even sub-clinical levels of deficiency - levels below recommended values but high enough to prevent the onset of more severe clinical systems - may lead to long-term problems. And whether it's macros or your micros, we tend not to eat within recommended intake levels.
But personalizing your diet by recognizing your specific intake levels and adjusting accordingly can help maintain long-term health. So eat a well-balanced diet, and pay particular attention to a few of these special cases if you fall into one of these groups. Stay active, and mind your nutrition.