Irritable bowel syndrome (IBS) is a type of functional gastrointestinal (GI) disorder. These conditions, also called disorders of the gut-brain interaction, have to do with problems in how your gut and brain work together. These problems cause your digestive tract to be very sensitive. They also change how your bowel muscles contract.
IBS is the most frequently diagnosed gastrointestinal disorder. Although symptoms can vary from patient to patient, they commonly include cramping, abdominal pain, bloating, intestinal gas, and diarrhea or constipation, or both. The disorder affects more women than men and is most common in people under 50. The annual medical costs of the condition exceed $1 billion in the United States alone.
Experts estimate that about 10% to 15% of the adult population in the United States have IBS. However, only 5% to 7% receive an IBS diagnosis.
IBS is a chronic condition that requires continual management strategies. The emotional distress it can cause often results in depression and anxiety.
One good finding is that IBS does not cause changes in bowel tissue or increase your risk of colorectal cancer.
Small intestinal bacterial overgrowth (SIBO) happens when bacteria that is usually found in the large intestine or elsewhere in the body starts to grow in the small intestine, resulting in the improper breakdown of certain foods. SIBO can impact your gut health in many different ways and, in some cases, can lead to malnutrition. While what causes SIBO is an excess of bacteria, there are many conditions that can lead to SIBO – like irritable bowel syndrome.
SIBO and IBS are separate medical conditions, but they commonly coexist, can be connected, and share similar symptoms. That means that if you have been diagnosed with IBS, there is a strong likelihood that you have SIBO, as well – approximately 80% of IBS patients also have SIBO. In some cases, SIBO is a result of IBS, but in other cases, it’s not. IBS and SIBO are also distinct based on the type of testing that is required to diagnose each. (Breath test for SIBO and an antibody blood test to diagnose IBS.)
The precise cause of IBS isn’t known. Factors that appear to play a role include:
- Muscle contractions in the intestine. The walls of the intestines are lined with layers of muscle that contract as they move food through your digestive tract. Contractions that are stronger and last longer than normal can cause gas, bloating and diarrhea. Weak intestinal contractions can slow food passage and lead to hard, dry stools.
- Nervous system. Abnormalities in the nerves in your digestive system may cause you to experience greater than normal discomfort when your abdomen stretches from gas or stool. Poorly coordinated signals between the brain and the intestines can cause your body to overreact to changes that normally occur in the digestive process, resulting in pain, diarrhea or constipation.
- Brain-gut dysfunction: Miscommunication between nerves in the brain and gut.
- Severe infection. IBS can develop after a severe bout of diarrhea (gastroenteritis) caused by bacteria or a virus. IBS might also be associated with a surplus of bacteria in the intestines (bacterial overgrowth).
- Early life stress. People exposed to stressful events, especially in childhood, tend to have more symptoms of IBS.
- Changes in gut microbes. Examples include changes in bacteria, fungi and viruses, which normally reside in the intestines and play a key role in health. Research indicates that the microbes in people with IBS might differ from those in healthy people.
Symptoms of both SIBO and IBS can be triggered by:
- Food. The role of food allergy or intolerance in IBS isn’t fully understood. A true food allergy rarely causes IBS. But many people have worse IBS symptoms when they eat or drink certain foods or beverages, including wheat, dairy products, citrus fruits, beans, cabbage, milk and carbonated drinks.
- Stress. Most people with IBS experience worse or more-frequent signs and symptoms during periods of increased stress. But while stress may aggravate symptoms, it doesn’t cause them.
Many people have occasional signs and symptoms of SIBO and IBS. But you’re more likely if you:
- Are young. IBS occurs more frequently in people under age 50.
- Are female. In the United States, IBS is more common among women. Estrogen therapy before or after menopause also is a risk factor for IBS.
- Have a family history of IBS. Genes may play a role, as may shared factors in a family’s environment or a combination of genes and environment.
- Have anxiety, depression or other mental health issues. A history of sexual, physical or emotional abuse also might be a risk factor.
Many people find that with these changes, symptoms improve:
- Increase fiber in your diet – eat more fruits, vegetables, grains and nuts.
- Drink plenty of water – eight 8-ounce glasses per day.
- Avoid caffeine (from coffee, chocolate, teas and sodas).
- Limit cheese and milk. Lactose intolerance is more common in people with IBS. Make sure to get calcium from other sources, such as broccoli, spinach, salmon or supplements.
- Try the low FODMAP diet. FODMAP stands for fermentable oligosaccharides, disaccharides, monosaccharides and polyols, which are short-chain carbohydrates (sugars) that the small intestine absorbs poorly.
People who have IBS and SIBO tend to avoid vegetables because eating them makes their symptoms worse. However, vegetables are very good for your gut flora, and therefore may be good for your IBS.
Start by gradually eating more vegetables that are less likely to cause gas and bloating. FODMAP researchers from Monash University in Australia have studied and identified which vegetables are suitable. They have organized an app that is easy to refer to while shopping. The app tells you how much of each food is safe before it might trigger a negative response.
Ideally, you would start with the vegetables on the following list and then slowly broaden the range of vegetables that you eat:
- Bamboo shoots
- Bell peppers
- Corn (half a cob)
- Green beans
- Scallions (green parts only)
- Sweet potato
- Water chestnut
You may find that cooked vegetables are more gentle on your gut than raw vegetables. You can steam, sauté, or roast them and avoid any spices you are sensitive to.
Your gut flora will be grateful if, along with eating more vegetables, you also eat more leafy greens. Leafy greens are packed with nutrients and are unlikely to cause gut fermentation, making them low-FODMAP foods. If you can tolerate them raw, leafy greens can be added to green smoothies, green juices, or made into a salad. But if you are like most people with IBS, you may find that your body is less reactive if the greens are cooked.
The easiest way to do this is to sauté or roast them with some olive oil.
- Arugula (rocket lettuce)
- Bok choy
- Collard greens
- Common cabbage
- Spinach (baby)
- Swiss chard
Like vegetables, fruits have some nutrients that are good for your gut flora and should be good for your IBS. But as you may have found out the hard way, some fruits are likely to make your IBS symptoms worse.
Choosing low-FODMAP fruits is a safer way to go. Just don’t eat too many in one sitting or within one day. Doing so may overwhelm your body’s ability to absorb the sugar in fruit without fermentation and gas.
- Avocado (limit 1/8 of a whole)
- Honeydew melon
- Mandarin oranges
- Papaya (pawpaw)
Nuts are a good source of fiber, protein, and anti-inflammatory omega-3 fatty acids. Nuts make you feel full after a meal or snack.
Nuts do contain unsaturated fat, but this fat is good for you as it lowers cholesterol. It is also good for your gut flora and may help your IBS. You can enjoy nuts by the handful or in the form of nut butters.
Here are some low-FODMAP nuts to get you started:
- Almonds (limit 10)
- Brazil nuts
- Hazelnuts (limit 10)
- Macadamia nuts
- Pine nuts
Of all the various types of seeds, chia seeds and flaxseed seem to benefit people with IBS most, especially those who tend to get constipated. Both seeds are a good source of fiber and omega-3 fatty acids.
You can sprinkle them on top of salads or oatmeal, or add them to your smoothies, just make sure to ground the flaxseeds up first.
For snacking, the following seeds are low in FODMAPs:
Some lifestyle changes might help alleviate SIBO amend IBS symptoms:
- Exercise regularly.
- Don’t smoke.
- Try relaxation techniques. There is a known connection between the brain and the gut, and undue stress can certainly aggravate the symptoms of SIBO and IBS. Cognitive behavioral therapy may benefit some patients, and many find it helpful to practice relaxation techniques like positive imagery, progressive muscle relaxation or meditation.
- Eat smaller meals more often.
- Record the foods you eat so you can figure out which foods trigger flare-ups.
Brazil nuts come from the South American Bertholletia excelsa, or Brazil nut, tree. They are a good source of healthful fats, protein, fiber, and selenium.
Despite its name, the Brazil nut is technically a seed rather than a nut. By definition, nuts are hard-shelled fruits that contain a single, large seed. (Walnuts and pistachios are good examples.)
Brazil nuts have a smooth, buttery texture and nutty flavor. These nuts are energy dense, highly nutritious, and one of the most concentrated dietary sources of the mineral selenium.
A 1-ounce serving of Brazil nuts contains the following nutrients:
- Calories: 187
- Protein: 4.1 grams
- Fat: 19 grams
- Carbs: 3.3 grams
- Fiber: 2.1 grams
- Selenium: 988% of the Reference Daily Intake (RDI)
- Copper: 55% of the RDI
- Magnesium: 33% of the
- Phosphorus: 30% of the RDI
- Manganese: 17% of the RDI
- Zinc: 10.5% of the RDI
- Thiamine: 16% of the RDI
- Vitamin E: 11% of the RDI
Brazil nuts are rich in selenium, with just one nut containing 96 mcg, or 175% of the RDI. Most other nuts provide less than 1 mcg, on average. The RDI for selenium is 55 mcg per day for adults.
Selenium is a trace element that is vital for the proper functioning of your body. It is essential for your thyroid and influences your immune system and cell growth. Higher levels of selenium have been linked to enhanced immune function and better outcomes for cancer, infections, infertility, pregnancy, heart disease, and mood disorders.
The thyroid is a small, butterfly-shaped gland that lies in your throat. It secretes several hormones that are essential for growth, metabolism, and body temperature regulation. Thyroid tissue has the highest concentration of selenium, as it’s required for the production of the thyroid hormone T3, as well as proteins that protect your thyroid from damage.
Selenium deficiency can cause hormonal imbalances that can negatively affect sleep, mood, concentration, and metabolism. Obtaining enough selenium from dietary sources may prevent or help regulate thyroid problems, such as hypothyroidism.
Brazil nuts have higher concentrations of magnesium, copper, and zinc than most other nuts, although the exact amounts of these nutrients can vary depending on climate and soil.
Brazil nuts are an excellent source of healthy fats. In fact, 36% of the fats in Brazil nuts are 37% polyunsaturated fatty acids which benefit heart health. Brazil nuts contain healthful fats called polyunsaturated and monounsaturated fatty acids. According to the American Heart Association (AHA), consuming monounsaturated fats and polyunsaturated fats instead of saturated and trans fats helps improve cholesterol levels, which lowers the risk of heart disease and stroke.
Brazil nuts also provide dietary fiber. The AHA report that eating fiber-rich foods improves blood cholesterol levels and lowers the risk of heart disease, stroke, obesity, and type 2 diabetes. The findings of a 2019 study showed that higher consumption of tree nuts decreased the risk of cardiovascular disease and heart attack among people living with diabetes.
Brazil nuts may boost the body’s antioxidant system and prevent oxidative stress. The liver breaks selenium down into a type of protein called selenoprotein P, which effectively removes excess free radicals. Free radicals cause oxidative stress, and research has linked them to many chronic health conditions, including cancer.
A double-blind, placebo-controlled study examined the antioxidant effects of Brazil nut consumption. During the study, 91 people with hypertension and high blood-lipid concentrations received either 13 g of granulated, partially defatted Brazil nuts or a placebo every day for 12 weeks. The participants in the Brazil nut group had higher selenium levels and increased activity of an antioxidant enzyme called GPx3. They also had lower levels of oxidized low-density lipoprotein (LDL).
Brazil nuts are rich in antioxidants, which are substances that help keep your cells healthy. They do this by combating damage caused by reactive molecules called free radicals. Brazil nuts contain several antioxidants, including selenium, vitamin E, and phenols like gallic acid and ellagic acid.
The selenium in Brazil nuts increases levels of an enzyme known as glutathione peroxidase (GPx), which helps reduce inflammation and protect your body from oxidative stress. One study in 10 people noted that a single 20- or 50-gram serving (4 or 10 nuts, respectively) significantly reduced a number of inflammatory markers, including interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-alpha).
Another three-month study gave people undergoing treatment for kidney failure one brazil nut per day. It found that their selenium and GPx levels had increased, while their levels of inflammatory markers and cholesterol had significantly decreased.
Brazil nuts contain ellagic acid and selenium, both of which can benefit your brain. Ellagic acid is a type of polyphenol in Brazil nuts. It has both antioxidant and anti-inflammatory properties that may have protective and antidepressant effects on your brain.
Low selenium levels are associated with neurodegenerative diseases like Alzheimer’s and Parkinson’s. In one study, older adults with mental impairment ate one Brazil nut per day for six months. In addition to experiencing increased selenium levels, they showed improved verbal fluency and mental function.
Supplementing with selenium may help mediate a poor mood, which is significantly associated with inadequate selenium intake.
Brazil nuts offer some impressive health benefits, but eating too many could be harmful.
*An intake of 5,000 mcg of selenium, which is the amount in approximately 50 average-sized Brazil nuts, can lead to toxicity. This dangerous condition is known as selenosis and can cause breathing problems, heart attack, and kidney failure. Too much selenium, particularly from supplements, has been linked to an increased risk of diabetes and prostate cancer.
To avoid consuming too much selenium, limit your intake to one to three Brazil nuts per day.
How to Buy
Most grocery stores carry Brazil nuts. Look for them in your local co-op in the bulk section or online at nuts.com.
How to Store
To preserve the quality of Brazil nuts, keep them away from onions and other high-odor foods. They tend to take on the smell of things around them. Store nuts at room temperature for up to three months. Store shelled or unshelled nuts in the refrigerator for up to six months, or in the freezer for a year or more. Label your packages of nuts with the date that they were put into storage, so you know which ones to use first.
If your nuts start to taste stale, toast them in a 350-degree oven for 10 minutes. It’ll bring back their flavor. Don’t expect it to improve rancid nuts. Once the oils in nuts go bad, there’s no fixing them.
How to Cook
People can eat whole Brazil nuts as a snack or add them to other foods. Brazil nuts are fine to eat raw or roasted.
To cook Brazil nuts on the stovetop:
- Place a layer of Brazil nuts in a skillet over medium heat.
- Stir the nuts every minute or so to avoid burning them.
- Continue cooking for about 5 to 10 minutes until the nuts become aromatic.
To roast Brazil nuts in the oven:
- Preheat the oven to 350°F.
- Place the nuts on a layer of parchment paper on a baking sheet.
- Place the baking sheet in the preheated oven and roast for 5 minutes.
- Take the baking sheet out of the oven and stir the nuts.
- Return the baking sheet to the oven for another 5 minutes.
- Remove the nuts from the oven and season them with salt, herbs, or spices.
- Allow the nuts to cool completely before eating them.
Try adding Brazil nuts to pad Thai dishes, trail mixes, or pesto. Alternatively, they can use chopped Brazil nuts as a topping for oatmeal, salads, or even brownies.
Coconut Mango and Brazil Nut Muffins
- 1 tbsp ground flaxseed + 3 tbsp water
- 3/4 cup plant-based milk
- 1 tbsp lemon juice
- 1/2 cup coconut sugar
- 1/4 cup coconut oil, melted and cooled
- 1 tsp vanilla essence
- 1 ½ cups all purpose gluten free flour
- 1/2 cup almond flour
- 2 tsp baking powder
- 1/4 cup desiccated coconut
- 1/2 tsp cinnamon
- A pinch of salt
- 1/2 cup chopped dried mango
- 1/4 cup + 1 tbsp chopped Brazil nuts
- 1/4 flaked coconut
- 1/2 cup powdered sugar
- 1-2 tbsp water
- Preheat the oven to 350 and line 12 muffin holes with cases.
- Stir together the ground flaxseed and water. Leave for 5 minutes to thicken.
- Meanwhile, to a large mixing bowl, add the plant-based milk and lemon juice and leave for 5 minutes.
- Add the coconut sugar, cooled melted coconut oil, vanilla and ground flaxseed. Whisk to a smooth mix.
- Sift in the gluten-free flour, baking powder and cinnamon.
- Add almond flour, desiccated coconut and salt. Whisk to a smooth, thick batter.
- Fold in the chopped mango and 1/4 cup of the chopped Brazil nuts. Use an ice cream scoop or large spoon to divide the batter between the 12 cases. Top with the extra tablespoon of chopped Brazil nuts.
- Bake for 15-17 minutes or until golden and toothpick comes out clean. Cool fully on a wire rack.
- Stir together the icing sugar and water and drizzle over the muffins before eating. Store in an airtight container for 3-5 days or freeze for 1 month.