Side Effects of Spinach

Image Credit: Anna Pustynnikova/iStock/GettyImages Loaded with vitamins and minerals, spinach has emerged as one of the healthiest foods on earth. It’s low in calories, fills you up quickly and can be prepared in a multitude of ways. As with everything else, moderation is key. Eating too much spinach may cause digestive distress and promote the formation of kidney stones due to its high oxalate content. The fiber in spinach can lead to bloating and stomach pain.

  Advertisement
 Read more: Can I Eat Spinach Every Day?

  Video of the Day
  
Spinach and Kidney Health

Along with kale, beets and most nuts, spinach is a stone-forming food. This veggie boasts high levels of oxalates, which are waste products of metabolism. During digestion, oxalates bind to calcium in the GI tract, reducing its absorption. These compounds are naturally eliminated in the urine or stool.

  Advertisement
 A high intake of oxalates may cause kidney stones. According to a 2015 review published by the Korean Society of Clinical Nutrition, crystals start to form when oxalate concentration is four times above normal. Most calcium stones in the kidneys consist of calcium oxalate. Research shows that high-oxalate foods, such as spinach and rhubarb, promote stone formation. About half of the people who develop one stone tend to form another within 10 years.

Nuts, potatoes and spinach account for 44 percent of oxalate intake for most Americans, according to a 2014 study published by the Korean Urological Association. That’s why health experts recommend eating these foods in moderation. The same study suggests that drinking more fluids may lower the risk of kidney stone formation.

  Advertisement
 Ideally, boil the spinach before consumption to reduce its oxalate levels. Cutting back on salt and meat may help too. These foods have been linked to a higher risk of kidney stones.

Effects of Spinach on Digestion

A bunch of raw spinach provides approximately 7.5 grams of fiber. That’s about one-third of the daily recommended intake based on a 2,000-calorie diet. As noted by the Mayo Clinic, this nutrient promotes digestive health, prevents constipation and slows sugar absorption into your bloodstream.

  Advertisement
 Too much fiber, on the other hand, can have the opposite effect. According to an article published by Duke University, eating more than 70 grams of fiber per day may cause bloating, gas, diarrhea, constipation, stomach cramps and other gastrointestinal symptoms. Plus, it fills you up quickly and curbs appetite, which may lead to unintentional weight loss.

  Advertisement
 Read more: Spinach and Stomach Cramps

  Advertisement
 Some studies suggest that fiber may interfere with vitamin and mineral absorption. However, the research is mixed. Since this nutrient is considered safe, no upper level of intake has been set.

The fiber in spinach can help you maintain a healthy weight, suppress appetite and keep your digestive system running smoothly. Some individuals may experience gastrointestinal symptoms, but this may or may not happen to you.

  Advertisement
 Do a quick online search for "spinach gas," "spinach diarrhea" or "spinach digestion" and you'll see that the effects vary from one person to another. Increasing your fiber intake suddenly, for example, is more likely to cause digestive distress than gradually adding more fiber to your diet.

Read more: Spinach and Diarrhea

Other Potential Side Effects

Since this veggie is high in fiber, it may reduce your blood sugar levels. This may lower your risk of diabetes, insulin resistance, heart disease and other ailments. However, if you’re taking anti-diabetes medications and eating high-fiber foods, you may experience hypoglycemia, or low blood sugar. Consult your doctor to determine whether spinach is safe for you.

  Advertisement
 If you're allergic to salicylates, you may not be able to eat certain fruits and veggies. As WedMD notes, these compounds occur naturally in spinach, eggplant, radishes, cruciferous vegetables, avocados, apples, peanuts and other foods. The most common allergic reactions include nasal congestion, swelling of the face and limbs, headaches, difficulty breathing, skin rash and itching.

When consumed in moderation, spinach is a healthy addition to most diets. If you experience bloating and indigestion, try to downsize your portions. Remember to drink plenty of water so you can fully reap the benefits of fiber.

  Advertisement
 
  Advertisement
  
  references & resources
  
      Harvard Medical School: 5 Steps for Preventing Kidney Stones
    
      K-State Research and Extension: Spinach and Kidney Stones
    
      Vegan Health: Calcium Absorption From Plant Foods
    
      Clinical Nutrition Research: Nutritional Management of Kidney Stones (Nephrolithiasis)
    
      The Korean Journal of Urology: Medical and Dietary Therapy for Kidney Stone Prevention
    
      Tufts University Health and Nutrition Letter: Should I Avoid Eating Spinach Because It Has Oxalate Found in Kidney Stones?
    
      SELF Nutrition Data: Raw Spinach
    
      Mayo Clinic: Dietary Fiber: Essential for a Healthy Diet
    
      Duke Student Health Nutrition Services: Fiber-How
    
      Australian Government Ministry of Health: Nutrient Reference Values: Dietary Fibre
    
      BioMed Research International: Hypoglycemic and Hypolipidemic Potential of a High Fiber Diet in Healthy versus Diabetic Rabbits
    
      WebMD: What Is a Salicylate Allergy?
    
      Kidney.org: What Are Oxalates and Why Are They a Concern for Kidney Disease Patients?
    
      Medill Reports Chicago: Kale Sheds Bum Rap on Kidney Stones
       




  references & resources
  
      Harvard Medical School: 5 Steps for Preventing Kidney Stones
    
      K-State Research and Extension: Spinach and Kidney Stones
    
      Vegan Health: Calcium Absorption From Plant Foods
    
      Clinical Nutrition Research: Nutritional Management of Kidney Stones (Nephrolithiasis)
    
      The Korean Journal of Urology: Medical and Dietary Therapy for Kidney Stone Prevention
    
      Tufts University Health and Nutrition Letter: Should I Avoid Eating Spinach Because It Has Oxalate Found in Kidney Stones?
    
      SELF Nutrition Data: Raw Spinach
    
      Mayo Clinic: Dietary Fiber: Essential for a Healthy Diet
    
      Duke Student Health Nutrition Services: Fiber-How
    
      Australian Government Ministry of Health: Nutrient Reference Values: Dietary Fibre
    
      BioMed Research International: Hypoglycemic and Hypolipidemic Potential of a High Fiber Diet in Healthy versus Diabetic Rabbits
    
      WebMD: What Is a Salicylate Allergy?
    
      Kidney.org: What Are Oxalates and Why Are They a Concern for Kidney Disease Patients?
    
      Medill Reports Chicago: Kale Sheds Bum Rap on Kidney Stones
    




Side Effects of Spinach

Image Credit: Anna Pustynnikova/iStock/GettyImages

Image Credit: Anna Pustynnikova/iStock/GettyImages

      Harvard Medical School: 5 Steps for Preventing Kidney Stones
    
      K-State Research and Extension: Spinach and Kidney Stones
    
      Vegan Health: Calcium Absorption From Plant Foods
    
      Clinical Nutrition Research: Nutritional Management of Kidney Stones (Nephrolithiasis)
    
      The Korean Journal of Urology: Medical and Dietary Therapy for Kidney Stone Prevention
    
      Tufts University Health and Nutrition Letter: Should I Avoid Eating Spinach Because It Has Oxalate Found in Kidney Stones?
    
      SELF Nutrition Data: Raw Spinach
    
      Mayo Clinic: Dietary Fiber: Essential for a Healthy Diet
    
      Duke Student Health Nutrition Services: Fiber-How
    
      Australian Government Ministry of Health: Nutrient Reference Values: Dietary Fibre
    
      BioMed Research International: Hypoglycemic and Hypolipidemic Potential of a High Fiber Diet in Healthy versus Diabetic Rabbits
    
      WebMD: What Is a Salicylate Allergy?
    
      Kidney.org: What Are Oxalates and Why Are They a Concern for Kidney Disease Patients?
    
      Medill Reports Chicago: Kale Sheds Bum Rap on Kidney Stones