Vitamin deficiency anemia

Overview

Vitamin deficiency anemia is a lack of healthy red blood cells caused by lower than usual amounts of vitamin B-12 and folate.

This can happen if you don't eat enough foods containing vitamin B-12 and folate, or if your body has trouble absorbing or processing these vitamins.

Without these nutrients, the body produces red blood cells that are too large and don't work properly. This reduces their ability to carry oxygen.

Symptoms can include fatigue, shortness of breath and dizziness. Vitamin supplements, taken by pill or injection, can correct the deficiencies.

Symptoms

Vitamin deficiency anemia usually develops slowly over several months to years. Signs and symptoms may be subtle at first but usually increase as the deficiency worsens. These may include:

  • Fatigue
  • Shortness of breath
  • Dizziness
  • Pale or yellowish skin
  • Irregular heartbeats
  • Weight loss
  • Numbness or tingling in the hands and feet
  • Muscle weakness
  • Personality changes
  • Unsteady movements
  • Mental confusion or forgetfulness

Causes

Vitamin deficiency anemia can occur if you don't eat enough foods containing vitamin B-12 and folate, or if your body has trouble absorbing or processing these vitamins.

Vitamin B-12 deficiencies

Low levels of vitamin B-12 can be caused by:

  • Diet. Vitamin B-12 is mainly found in meat, eggs and milk, so people who don't eat these types of foods may need to take B-12 supplements. Some foods have been fortified with B-12, including some breakfast cereals and some nutritional yeast products.
  • Pernicious anemia. This condition occurs when the body's immune system attacks cells in the stomach that produce a substance called intrinsic factor. Without this substance, B-12 can't be absorbed in the intestines.
  • Gastric surgeries. If portions of your stomach or intestines have been surgically removed, that can reduce the amount of intrinsic factor produced and the amount of space available for vitamin B-12 to be absorbed.
  • Intestinal problems. Crohn's disease and celiac disease can interfere with absorption of vitamin B-12, as can tapeworms that may be ingested from eating contaminated fish.

Folate deficiencies

Also known as vitamin B-9, folate is a nutrient found mainly in dark green leafy vegetables and liver. A folate deficiency can occur when people don't eat foods containing folate or their bodies are unable to absorb folate from food.

Absorption problems may be caused by:

  • Intestinal diseases such as celiac disease
  • Surgical removal or bypass of a large part of the intestines
  • Excessive alcohol consumption
  • Prescription drugs, such as some anti-seizure medications

Pregnant women and women who are breastfeeding have an increased demand for folate, as do people undergoing dialysis for kidney disease.

A lack of folate can cause birth defects during pregnancy. However, folate deficiency is less common now in countries that routinely add folate to food products such as breads, cereals and pasta.

Complications

Being deficient in vitamin B-12 or folate increases your risk of many health problems, including:

  • Pregnancy complications. A developing fetus that doesn't get enough folate from its mother can develop birth defects of the brain and spinal cord.
  • Nervous system disorders. Untreated, vitamin B-12 deficiency can lead to neurological problems, such as persistent tingling in the hands and feet or problems with balance. It can lead to mental confusion and forgetfulness because vitamin B-12 is necessary for healthy brain function.
  • Gastric cancer. Pernicious anemia increases the risk of stomach or intestinal cancers.

Prevention

You can prevent some forms of vitamin deficiency anemia by choosing a healthy diet that includes a variety of foods.

Foods rich in vitamin B-12 include:

  • Beef, liver, chicken and fish
  • Eggs
  • Fortified foods, such as breakfast cereals
  • Milk, cheese and yogurt

Foods rich in folate include:

  • Broccoli, spinach, asparagus and lima beans
  • Oranges, lemons, bananas, strawberries and melons
  • Enriched grain products, such as bread, cereal, pasta and rice
  • Liver, kidneys, yeast, mushrooms and peanuts

Most adults need these daily dietary amounts of the following vitamins:

  • Vitamin B-12 — 2.4 micrograms (mcg)
  • Folate or folic acid — 400 mcg

Pregnant and breastfeeding women may require more of each vitamin.

Most people get enough vitamins from the foods they eat. But if your diet is restricted or you've had gastric bypass surgery, you may wish to take a multivitamin.

Diagnosis

To help diagnose vitamin deficiency anemias, you might have blood tests that check for:

  • The number and appearance of red blood cells
  • The amount of vitamin B-12 and folate in the blood
  • The presence of antibodies to intrinsic factor, which indicates pernicious anemia

Treatment

Vitamin deficiency anemia is treated with doses of whichever vitamin is lacking. For pernicious anemia, vitamin B-12 is usually delivered via injection and may need to be taken regularly for the rest of your life.

Vitamin B-12 is available as:

  • Injections into a muscle or under the skin
  • Pills to be swallowed
  • A liquid or tablet that dissolves under the tongue
  • Nose gel or sprays

Medications to boost folate levels usually come as pills to be swallowed, but some versions can be delivered through a narrow, flexible tube into a vein (intravenously).

Preparing for an appointment

If you suspect that you have vitamin deficiency anemia, you're likely to start by seeing your family doctor or a general practitioner. However, in some cases, you may be referred to a doctor who specializes in treating blood disorders (hematologist).

Here's some information to help you get ready for your appointment and what to expect from your doctor.

What you can do

  • Write down any symptoms you're experiencing, including any that may seem unrelated to the reason for which you scheduled the appointment.
  • Write down key personal information, including any major stresses or recent life changes.
  • Make a list of all medications as well as any vitamins or supplements you're taking.
  • Write down questions to ask your doctor.

Your time with your doctor is limited, so preparing a list of questions will help you make the most of your time together. For vitamin deficiency anemia, some basic questions to ask your doctor include:

  • What's the most likely cause of my symptoms?
  • Could anything else be causing my symptoms?
  • Is my condition likely temporary or long lasting?
  • What treatment do you recommend?
  • Are there any alternatives to the approach that you're suggesting?
  • I have another health condition. How can I best manage these conditions together?
  • Are there any foods I need to add to my diet?
  • Are there any brochures or other material that I can take with me? What websites do you recommend?

In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask questions during your appointment anytime that you don't understand something.

What to expect from your doctor

Your doctor is likely to ask you a number of questions. Being ready to answer them may reserve time to go over points you want to spend more time on. Your doctor may ask:

  • When did you begin experiencing symptoms?
  • How severe are your symptoms?
  • Does anything seem to improve your symptoms?
  • What, if anything, appears to worsen your symptoms?
  • Are you a vegetarian?
  • How many servings of fruits and vegetables do you usually eat in a day?
  • Do you drink alcohol? If so, how often, and how many drinks do you usually have?
  • Are you a smoker?

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