All fruits and vegetables do not offer an equal amount of similar nutrients. Some vegetables could be detrimental to your gut health. So, while you should amp up your intake of whole and organic foods, some veggies you should consume in small quantities.
Your Gut Health- What Factors to Consider?
The human gut is a complex microenvironment and is home to trillions of bacteria. Also, the gut contains secretions with a variety of enzymes digesting carbohydrates, proteins, and fats.
Many studies have shown that diverse gut microbiota is beneficial for many aspects of human health. Unfortunately, the western diet reduces the diversity of your gut microbiota and contains anti-nutrients (1).
There is a bi-directional link between your gut health and your lifestyle; that is, your eating habits dictate your gut health, and the nature of your gut microenvironment decides what kind of foods would suit you (2). (You can learn more about the gut microenvironment in our article “The Best Time to Take Probiotics.”)
The idea behind eating a balanced diet with a mixture of fruits and vegetables is to promote the diversity of your gut microbiota. Generally speaking, vegetables of all kinds are great at promoting a healthy, diverse gut microbiota. However, some vegetables may actually be harmful to certain people who are either intolerant to those types of vegetables or eat them in too high a quantity.
Vegetables That Affect Your Gut Health
Given the traditional western-style diet is perhaps not the best diet, you might want to start eating ‘all-natural.’ But there is a catch! What suits others might not suit you at all.
Just like your fingerprints, no two people share the same gut microbiota (3). That means your gut might not tolerate a few vegetables and you might want to cut back on them.
What vegetables can be bad for your gut? Here is what we know from research.
1. Cruciferous Vegetables
The vegetables in this group include:
- Collard greens
- Brussels sprouts
These green vegetables are an abundant source of fiber, which helps your gut move. However, high fiber content can pose a threat to your gut health if you have a sensitive gut or Irritable Bowel Syndrome (IBS).
There are two main types of dietary fiber: soluble and insoluble dietary fiber. Soluble dietary fibers are rapidly but partly digested and lead to the production of gas. Insoluble dietary fiber, on the other hand, remains undigested as it passes through the gut (4).
Cruciferous vegetables contain a high amount of fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs). For instance, these vegetables contain sugars such as mannitol and sorbitol. The human gut does not contain the enzymes needed to digest these sugars. These sugars are partly fermented and lead to gas production (5).
Besides, gut conditions such as IBS are characterized by an imbalance in gut bacteria called dysbiosis. Individuals with IBS have higher Firmicutes/Bacteroidetes ratio, and this dysbiosis is often the critical pathology in IBS (6). Recent studies have suggested that taking a low FODMAP can improve the gut microbiota balance for the better and can reduce gut symptoms in IBS by 50 percent (7).
2. Roots and Tubers
The following are the roots and tubers that may be affecting your gut health.
Like cruciferous vegetables, roots are incredibly high in FODMAPs. In fact, roots such as onions, garlic, and ginger are perhaps the most concentrated sources of FODMAPs (8).
Also, these vegetables are a strong trigger for acid production in your stomach. In one research, when onions were given to individuals with heartburn, all 16 individuals suffered a significant worsening of acid reflux symptoms within two hours of ingesting onions (9).
3. Peas and Beans
The reason, again, is that peas are rich in sugars that are unfriendly for your gut. Peas are rich in mannitol. Humans don’t possess the enzymes needed for degrading this sugar. As a result, it reaches the gut and gets fermented there by the gut microbiota. As a result, you end up having an altered microbiota and worsening of your IBS symptoms (10).
Also, peas and beans are rich in anti-nutritional ingredients such as saponins. Saponins induce local inflammation in the gut. Research suggests that saponins from vegetables cause a local release of inflammatory chemicals such as interleukins. Also, these chemicals cause death (apoptosis) of cells lining the gut wall (11).
This makes your gut ‘leaky’ and permeable to toxins. The toxins can seep into your circulation and trigger an inflammatory response leading to inflammatory conditions.
Also, beans are rich in an anti-nutrition called phytic acid. Phytic acid chelates (binds to) nutrients such as zinc, magnesium, and iron and leads to a reduction in the absorption of these nutrients (12). Animal studies suggest that eating a diet rich in phytic acid can promote inflammation and reduce immunity inside the gut. When fish were given a diet rich in phytic acid, they experienced a striking increase in the levels of chemicals such as tumor necrosis factor α, interleukin, interferon. Also, it leads to a reduction in the levels of immunity-mediating proteins (13).
4. Nightshade Vegetables
Nightshade vegetables mainly include:
- Bell peppers
- Cayenne pepper
Eggplant, and all nightshade vegetables, for that matter, are another group of vegetables to avoid if you have digestive issues. Eggplant is high in an ingredient called ‘lectins.’ Lectins are proteins that can cause mayhem as far as your digestive health goes.
Lectins strip away the protective mucous layer of your gut. This layer protects your gut from the digestive enzymes and acts as a barrier for the harmful organisms. By stripping away this protective layer, lectins open-up the gateway to hell (literally) and make your gut leaky. Bacteria, toxins, and other harmful chemicals seep from your gut into your circulation and cause a variety of inflammatory and autoimmune disorders like rheumatoid arthritis and thyroid disease (14).
Also, lectins trigger a group of cells in your gut and stomach wall called the ‘mast cells.’ The secretions from these cells cause a dramatic increase in the amount of acid secreted from your stomach and increase the risk of stomach ulcers (14).
5. Potatoes and Tomatoes
These vegetables include anti-nutrients alkaloids such as solanine and chaconine. These alkaloids are abundant in the skin of potatoes and tomatoes. These alkaloids can have short and long-term effects on your gut health.
These alkaloids can cause local inflammation and can lead to gastrointestinal side effects such as abdominal pain and diarrhea. In the longer run, these alkaloids can induce apoptosis of the gut cells and reduce the barrier function of the intestinal mucosa. This can lead to increased intestinal inflammation and can worsen colitis (intestinal inflammation) (15). These vegetables are not the right choice for you if you have Inflammatory Bowel Disease (IBD).
Also, tomatoes and potatoes are high FODMAP foods and can worsen your abdominal symptoms if you have IBS. As a result, these vegetables can be bad for your gut health.
Should You Completely Eliminate These Vegetables From Your Routine?
There is no right answer to this question. There is no one-stop solution for everyone when it comes to nutrition.
There are a few factors to consider.
- Everyone is different: As mentioned before, every food does not suit everyone, and what might suit others might not be suitable for you.
- Find the vegetables that suit you: If you have IBS, then you should definitely avoid high FODMAP foods. However, if you are generally interested in maximizing your gut health and avoiding any potential food triggers, then you have to put some effort into this. You will have to find out the vegetables that suit you.
- Keep a food diary: Keep a food diary and start by eliminating one vegetable from your routine for one week. Keep repeating the process until you find the vegetable(s) that trigger abdominal symptoms.
Otherwise, if you believe you have a sensitive gut, then it is always better to eat these vegetables in moderations.
Also, always seek the advice of a qualified nutritionist or a healthcare provider before making any changes in your dietary regimen.
Tips to Improve Gut Health
Factors like diet, lifestyle, environmental elements, sleep, stress, alcohol and caffeine consumption, and levels of physical activity can negatively impact your gut health and cause constipation, diarrhea, belching, and bloating.
On the other hand, regular physical activity, low-stress levels, and a healthy diet can boost gut health and strengthen your immune system.
Remember, healthy gut flora is essential for physical and mental health. If you have developed digestive problems from consuming large portions of any of the vegetables listed above, the following are a few ways you can improve your gut health.
Have Quality Sleep
Every adult should sleep for at least eight hours every night.
To achieve good sleep, you may want to cut down your caffeine intake a good few hours before your bedtime. Try to go to bed at a fixed time each day to develop a routine. Sleep efficiency directly affects gut health, which is why you must improve your sleeping habits for a healthy digestive tract.
Consume Foods Rich in Probiotics
Foods rich in probiotics are healthy for your gut. They improve your digestive health and maintain the balance of friendly and harmful gut flora.
Fermented foods such as kimchi, tempeh, kefir, and yogurt are all excellent sources of probiotics. If that’s not enough, you can get started on probiotic supplements to maintain digestive health.
Reduce Stress and Exercise
Stress and lack of physical activity can cause digestive issues, too. Regular exercise, meditation, and reduction in stress levels may help you maintain good digestive health.
The food you eat can also affect your levels of cortisol (the stress hormone); read about foods that reduce cortisol levels in our article “Stay Calm with These Cortisol-Lowering Foods (Including Chocolate!).”
If your heightened stress levels frequently affect your gut and overall health, you should consider consulting a psychologist because increased stress levels affect gut health.
Final Verdict: Are All Vegetables Suitable for You?
All vegetables are not meant for everyone.
While vegetables of all kinds are generally good at promoting a diverse gut microbiota, some vegetables contain anti-nutrients and ingredients that may cause inflammation of the intestines in people who are sensitive to them.
Don’t go by everything you read on the internet. Every food might not suit you. So invest some time into trying to figure out what works best for your health.
We hope this article was an informative guide about vegetables bad for your gut and how you can combat the adverse effects by consuming foods rich in probiotics, having ample sleep, and doing regular exercise.