I doubt I need to tell you that nuts are healthy, but you might be surprised to learn that they contain a FODMAP called galacto-oligosaccharide (ie. GOS). Low FODMAP nuts contain small amounts of GOS so they shouldn’t trigger your IBS symptoms.
Despite their FODMAP content, nuts are nutrition powerhouses that I highly recommend you eat on a regular basis as part of a balanced diet. They’re an excellent source of healthy fats, a good source of fiber and protein, and contain numerous micronutrients.
Nuts also contain phytochemicals that reduce the risk of chronic disease, antioxidants that fight inflammation, and prebiotics that feed your gut bacteria.
Today we’re going to explore low FODMAP nuts, why nuts are kickass superfoods, and how to include them in your diet.
So get ready to make like a squirrel and get your nut on! 😉
4 reasons why you should eat low FODMAP nuts
1.Phytochemicals and antioxidants
1.a) Antioxidants
Antioxidants are natural substances that minimize cell damage caused by free radicals. Free radicals are molecules produced by metabolism, exercise and environmental factors that damage DNA. When not kept in check by antioxidants, free radicals can trigger oxidative stress which is a risk factor for chronic disease.
One especially potent antioxidant in nuts is vitamin E. Research on vitamin E suggests it may improve low grade inflammation associated with heart disease and diabetes. It may also reduce the risk of cancer and protect against neurodegenerative disease like Alzheimer’s.
There’s evidence that vitamin E may protect against neurodegenerative disease… Oops, forgot I already said that. Maybe I should eat more nuts… 😉
1.b) Phytochemicals
Phytochemicals are natural compounds found in plant foods such as fruits, vegetables, grains, nuts, seeds, spices, and herbs that exert positive effects on health. And guess what – nuts are rich sources of phytochemicals!
In particular, nuts contain significant amounts of polyphenols, which are known for their antioxidant activity. The scientific literature shows that polyphenols reduce the risk of heart disease, improve inflammation, and may be preventative against gastrointestinal diseases.
Since low grade inflammation is thought to play a role in irritable bowel syndrome, the positive impact of phytochemicals and antioxidants makes eating low FODMAP nuts a no-brainer.
2. Fibre and the gut microbiome
Your diet has a profound impact on your gut microbiome, and in turn, growing evidence suggests that your gut microbiome has a significant impact on your health.
So how lucky are you that nuts contain fibre and prebiotics that nourish your gut flora.
Although more research is needed, a review of the effect of nuts on the gut microbiota found an increase in bacteria that produce short-chain fatty acids (SCFAs). Walnuts are particularly effective at boosting these bacteria.
SCFAs promote the health of the large intestine, minimize inflammation, and contribute to healthier blood sugar and cholesterol levels.
3. Healthy fats
Nuts have a lot of fat, but in the fairly small recommended portion size of 1 to 1.5 oz, the total fat is fine. Besides, most of the fat in nuts consists of heart healthy mono-unsaturated fatty acids, aka MUFAs.
Nuts also contain poly-unsaturated fatty acids, aka PUFAs. You know these guys as omega-3s. Omega-3 fats are important for the health of your brain, eyes, and cardiovascular system. Once again, walnuts dominate in their omega-3 content.
It was once thought that the healthy fats in nuts played the primary role in reducing the risk for heart disease. While these fats do indeed promote cardiovascular health, we now know that phytochemicals, antioxidants and the rich micronutrient profile in nuts also contribute (27).
In addition to reducing risk of chronic disease, the fat in nuts helps your body absorb fat soluble vitamins like vitamin A, D, E, and K.
4. Micronutrients: vitamins and minerals
It would be quicker to list the micronutrients (ie. vitamins and minerals) that are NOT found in nuts!
Nuts are nutrient dense foods, meaning they’re jam packed with important vitamins, minerals, fats, proteins, and fibre. Nuts are especially good sources of minerals that contribute to heart and bone health.
Nuts are good sources of:
- Vitamin E
- B vitamins
- Selenium
- Magnesium
- Manganese
- Zinc
- Potassium
- Phosphorus
- Iron
7 low FODMAP nuts
During the elimination phase of the low FODMAP diet, when you’re replacing high FODMAP foods with low FODMAP foods, low FODMAP nuts are the way to go. And the good news is there are lots of options!
The portions listed below are low FODMAP serving sizes per the Monash University FODMAP app at the time of writing. If you eat larger servings, you risk entering moderate or high FODMAP territory.
A low FODMAP food list (including my list below!) can change when foods are re-tested, so you should always check the Monash app for the most up to date info.
1. Walnuts (30g or 10 walnut halves)
Walnuts are not only FODMAP friendly, but their polyphenol and omega-3 fatty acid content is the highest among the nuts. In fact, walnuts appear to be the health stars of the nut family. That being said, don’t limit yourself to only walnuts because then you don’t benefit from unique benefits of other nuts. Eating a variety of plant foods is how you win the nutrition game.
2. Peanuts (28g or 32 nuts)
Peanuts contain only trace amounts of FODMAPs, so you can eat them freely according to Monash. Unique to peanuts is their high arginine content. Arginine is an amino acid that strengthens the cell walls of the gastrointestinal tract. In other words, arginine may improve leaky gut which is suspected of playing a role in IBS.
3. Brazil nuts (40g or 10 nuts)
Current research suggests Brazil nuts don’t seem to have much effect on cholesterol, but they are incredibly rich in selenium which is a ravenous antioxidant. One Brazil nut contains more than the daily recommended amount of selenium. One! That’s rich.
4. Macadamia nuts (40g or 20 nuts)
Similar to peanuts, macadamias have very small amounts of FODMAPs so you can eat all the white chocolate macadamia cookies you want! Just joking. 😉 You can certainly eat a goodly amount of macadamias, but watch the cookie intake.
5. Pecans (20g or 10 pecan halves)
Pecans are second to walnuts in their polyphenol content so their antioxidant capacity is high. Polyphenols can also act as prebiotics in that they foster the growth of health-promoting bacteria such as Lactobacilli and Bifidobacterium.
6. Hazelnuts (15g or 10 nuts)
Research has found that the skin in hazelnuts is a rich source of the polyphenols, and when it is removed, polyphenol levels drop significantly. So if you plan on eating hazelnuts, leave the skin on!
7. Pine nuts (14g or 1 Tbsp)
Pine nuts are fairly high in omega-3s; however, in a 1 Tbsp portion, you’re not getting a large amount of any nutrient really. But it’s nice to know you can continue to enjoy pine nuts in basil pesto!
High FODMAP nuts
The main FODMAPs in nuts are galacto-oligosaccharides (GOS) and fructans. Avoid these nuts during the elimination phase of the low FODMAP diet.
Almonds (24g or 20 nuts)
Almonds are high in GOS, but a smaller serving size of 10 nuts is considered low FODMAP. This is convenient because eating exactly 10 almonds was once touted by the diet industry as the “magic bullet” of health (cue eye roll).
An interesting study did in fact find that 10 almonds per day eaten before breakfast can marginally improve HDL (ie. good cholesterol) in people with low HDL (a risk factor for heart disease).
Whether or not this finding is legit, we know almonds are indeed healthy, with high fibre and protein content, so you can add a few to a low FODMAP nut mix and reap some benefits.
Cashews (30g or 20 nuts)
There’s no low FODMAP serving size for cashews, which contain both GOS and fructans. Cashews sport the same nutrients, antioxidants and healthy fats as other nuts but in less exciting amounts, save for copper. Copper is an essential mineral and plays a role in many bodily processes.
Pistachios (15g or 15 nuts)
Tragically, pistachios contain high levels of GOS and fructans with no low FODMAP serving size. Pistachios are high in fibre, protein and two phytochemicals that contribute to eye health: leutin and zeaxanthin. I love pistachios and tend to eat them like Pringles – once you pop you can’t stop.
How to add low FODMAP nuts to your diet
Nuts can be part of a healthy snack or meal. I recommend you enjoy a healthy portion size of 1.5 oz or 45g on most days of the week.
- Nosh a small handful of mixed low FODMAP nuts for a morning snack.
- Add peanuts to your popcorn on movie night.
- Make your own trail mix with 1/4 cup low FODMAP nuts containing at least 1 Brazil nut, a few banana chips, 1 Tbsp raisins, 1 Tbsp chocolate chips and maybe some gluten-free Crispix cereal.
- Mix walnuts into muffins and pancakes.
- Toss low FODMAP nuts on salad.
- Top oatmeal or cereal with your favourite nuts.
- Sprinkle hazelnuts onto ice cream.
- Add walnuts to a rice pilaf or quinoa salad.
- Blend low FODMAP nuts into smoothies.
- Make homemade candied nuts for special occasions like Christmas.
- Enjoy pad thai with peanuts.
Frequently asked questions
Natural or roasted?
Research has found that polyphenol and antioxidant activity are generally highest in raw nuts, especially when their skins are intact and eaten. However, roasting can decrease or enhance antioxidant activity depending on the nut, temperature and duration of roasting. This is also true of polyphenol content.
The best advice I can give is – eat raw or roasted based on your preference, and focus instead on eating a variety of nuts on a regular basis.
One more note: some people develop a temporary itchy mouth or throat from eating certain nuts raw (eg. hazelnuts). This response is pollen food allergy syndrome (previously called oral allergy syndrome). Most people with this condition don’t experience symptoms with roasted nuts because the protein that triggers the response loses its potency after it has been heat treated.
Salted or unsalted?
Opt for unsalted nuts if you have high blood pressure, heart disease or chronic kidney disease.
A general rule of thumb for nutrients we want less of, like sodium and saturated fat, is to choose products where the portion size we plan to eat contains 5% or less of the % daily value based on the Nutrition Facts Table found on the food label.
So if you plan to eat 1/4 cup of salted peanuts and the % daily value is 6%, well, that’s pretty close and I’d say that’s fine. If the % daily value is 8+%, I’d suggest choosing the unsalted version, or diluting the sodium by having 2 Tbsp salted and 2 Tbsp unsalted (total 1/4 cup).
What about nut butters?
Research on the health benefits of nuts has mostly focused on whole nuts rather than nut butters. Of the few studies and reviews that evaluated nut butters, results were inconsistent. At this point, there isn’t good evidence to suggest that you can replace nuts with nut butters and reap the same health benefits.
This isn’t to say there are NO health benefits of nut butters. Not at all. Nut butters still contain important nutrients like healthy fats, protein, fibre, vitamin E, folate, magnesium, zinc, etc. But ultimately, we need more research on how nut butters influence our risk of chronic disease.
If you really love your nut butters, both natural and commercial (eg. Kraft) are nutritious. But in the interest of minimizing processed foods, give the natural versions a fair shot first.
Bottom line
- Low FODMAP nuts include walnuts, peanuts, Brazil nuts, hazelnuts, pecans, macadamias and pine nuts.
- High FODMAP nuts contain GOS and fructans, and include almonds, cashews and pistachios. Check for low FODMAP serving sizes in the Monash app to see if you can enjoy these nuts during the elimination phase of the low FODMAP diet.
- Eat roughly 1.5 oz (45g) of nuts most days of the week.
- Walnuts are king, but variety is the spice of life. 🙂
xoAndrea, RD
