As clinical nutritionists, we see clients who have been suffering with a variety of symptoms for months and even years. Is it food allergies or food intolerance? It may be hard to determine. We developed a food symptoms chart to help you learn the difference. But did you realize that it may be possible to overcome many food intolerances?
When it comes to identifying food allergies and food intolerances, it isn’t that people haven’t tried to find the right answers; people have commonly tried different elimination diets, medications, and supplements to get relief.
But unfortunately, our digestive health can be pretty darn complicated.
And on top of that: elimination diets are meant to manage symptoms and to determine triggers – they aren’t meant to be followed forever.
What you’ll discover is that it can take some real detective work to uncover why you’re experiencing these symptoms, to begin with. Doing this detective work is important, as this will determine your ability to have a solution that works long-term.
The symptoms that might be causing you grief – the gas, bloating, brain fog, and digestive discomfort – might be the symptoms of a food intolerance. But where things can get interesting is that the food might not be the true issue: you could be having a reaction to food because of poor gut health. And if you were able to optimize your digestive health, you should be able to tolerate many more foods with far fewer symptoms.
Let’s dive in with a common question: what is the difference between a food allergy and an intolerance?
Food Allergy vs. Food Intolerance
Food allergies and food intolerances are similar in that your body has a negative reaction to eating a food (1).
You might have a range of symptoms after eating certain foods. But, a food allergy and an intolerance are not the same thing. Allergies can be life threatening and you might never grow out of them.
In contrast, a food intolerance might actually be a symptom of poor gut health. In that case, you may be able to optimize your gut health and be able to better tolerate foods that have bothered you in the past – exciting, right?
Let’s dive in first with allergies.
What is a Food Allergy?
A food allergy is a BIG response from your immune system, usually in response to a protein in a food. You may have issues breathing; an allergic reaction can quickly become a medical emergency. About 2% of adults in the US have food allergies (2).
Symptoms of an allergic reaction tend to be fast and might include:
- Difficulty breathing
- Swelling of your lips and tongue
- Rash
- Hives
- Abdominal pain and cramps
- Vomiting and/or diarrhea
The most common food allergens are to (3):
- Wheat
- Milk
- Eggs
- Fish
- Shellfish
- Soy
- Sesame
- Tree Nuts
- Peanuts
Note: you can also have allergies to things in your environment, such as pollen, latex, and chemicals.
In our work, we help our clients suss out whether they have a food allergy or a food intolerance. As our client, we’ll partner with you to correctly identify the root causes of your current symptoms and craft a customized plan so that you can finally feel better.
For the rest of this article, we’ll focus on food intolerances.
What is a Food Intolerance?
A food intolerance happens when your gut is not able to properly digest something that you’re eating. An intolerance can happen when you’re missing an enzyme needed to digest your food (such as your body not making the lactase enzyme needed to digest lactose, the sugar in milk). An intolerance can also happen as a side-effect of something else. For example, if you have SIBO, your small intestine can become inflamed and your production of enzymes are compromised. You may no longer be making enough lactase enzyme to digest lactose. However, when you resolve and heal from SIBO, you may be able to tolerate lactose – without any symptoms – in the future.
An intolerance is not life-threatening, but the symptoms can have a big impact on your day. A food intolerance reaction is an overreaction of your body to a food, but not through the same immune pathway as an allergy.
An estimated 20% of adults in the US have a food intolerance (4).
The most common food intolerances we see in our practice include:
- Lactose
- Histamine
- Fructose
Symptoms of a food intolerance can include a wide variety of unpleasant things, but may take hours or even days to pop up. Signals of a food intolerance might include:
- Brain fog
- Nausea, vomiting, and diarrhea
- Skin issues, such as eczema
- Headache and migraine
- Cramps
- Gas
- Heartburn
What is Lactose Intolerance?
While we all have the ability to digest lactose as an infant, many of us lose some (or all) of our ability to digest lactose as adults. In fact, we estimate that 65% of the world’s population is lactose intolerant (5).
Lactose is found in dairy foods in varying amounts. Sources of lactose include:
- Milk
- Yogurt
- Kefir
- Cheese
- Ice-cream
Lactose intolerance symptoms tend to arrive 1-2 hours after a meal containing lactose and can include:
- Gas
- Abdominal pain
- Feeling of uncomfortable fullness
- Diarrhea
What is Histamine Intolerance?
So…what is histamine? Histamine is a normal chemical messenger that your body makes in response to an injury or potential allergen. That awful itching after a mosquito bite? Itchy nose, watery eyes, a rash…That’s histamine in action.
An estimated 1% of the US population has histamine intolerance (6).
If you have a healthy digestive tract, you have an enzyme called DAO that can help you break down and excrete histamine. But in the case of histamine intolerance, you’re making too much histamine and/or not making enough of the enzyme to clear histamine.
The result? A whole lotta histamine causing you to feel crummy. But what you may not realize is that histamine intolerance can actually cause a host of other symptoms such as:
- Bloating (very common!)
- Changes in body temperature
- Changes in heart rate
- Acid reflux
- Anxiety
- Nasal congestion
- Flushing
- Difficulty sleeping
What makes this intolerance a bit trickier to diagnose is that certain foods actually contain histamine. For example, the following foods all contain high levels of histamine: (7)
- Fermented foods like yogurt, miso paste, and kombucha
- Aged cheeses like cheddar, Gouda, parmesan
- Aged meats like steak, prosciutto, sausage
To learn more about histamine intolerance, check out this post: What the H3LL is Histamine Intolerance?
Next intolerance to investigate? Fructose intolerance.
What is Fructose Intolerance?
Fructose is a kind of sugar that is found naturally in fruit and honey but is also found in high amounts in processed foods, such as soda and packaged cookies (8). Because fructose is added to so many drinks and packaged foods, we’re eating far more than we realize…and it may have consequences for your digestive system.
As with lactose intolerance, fructose intolerance can happen because your body isn’t making the necessary enzyme to digest the fructose, or, your body would have made the enzyme, but some other condition is preventing it. Examples include uncontrolled celiac disease, a recent round of antibiotics, SIBO or high levels of stress (9).
Foods that are high in fructose include (10, 11):
- Fruit
- Fruit juice
- Honey
- High-fructose corn syrup
- Peas
- Zucchini
- Candy
- Ice cream
- Fast food
Symptoms of fructose intolerance come from the bacteria in your digestive tract fermenting the fructose sugar instead of your body absorbing it. Symptoms can include:
- Abdominal pain
- Gas
- Diarrhea
So far we’ve explored three of the most common food intolerances we see in our practice; lactose, histamine and fructose. Unfortunately, there can be more potential offenders! Another common cause of digestive symptoms are FODMAPs. FOD-what?
FODMAPs are a group of foods that contain specific carbohydrates that can cause a negative digestive reaction. Fructose and lactose are two examples of FODMAPs that we’ve already discussed in this blog post. Other examples of FODMAPs include the fructans in garlic and onions and the polyols in cherries and apples. People with IBS, SIBO and other digestive issues may have trouble digesting one or more FODMAP (12).
Food Intolerance Symptoms Chart
| Food allergy | Food intolerance | |
|---|---|---|
| Common food offenders | Milk Eggs Fish Shellfish Soy Wheat Sesame Tree Nuts Peanuts | Lactose Fructose Histamine Chemicals in food Other FODMAPs |
| Common symptoms | Difficulty breathing Swelling of your lips and tongue Hives Abdominal pain and cramps Vomiting and/or diarrhea | Abdominal pain Gas Diarrhea Bloating Anxiety Brain fog Heartburn (GERD) Headache and migraine |
| How fast? | Very quickly after eating the food | Symptoms can take hours or even days to emerge |
| Diagnostic options | Skin prick test Blood testing | Elimination diet Breath testing Stool testing Intestinal biopsy Note: blood tests for food sensitivities may not be accurate. |
| How common? | 2% of adults | 20% of adults |
| Is there a cure? | Not likely | Possibly, if you can uncover and treat the root cause. |
That wraps up a review of three of the most common food intolerances. What do they all possibly have in common? Sub-optimal digestive health.
Good news! We can help you craft a personalized plan to optimize your gut health and by proxy, increase the variety of foods that you’re able to enjoy without digestive complaint.
Let’s switch gears and discuss how functional nutrition can help you to uncover why you’re having a food intolerance to begin with – no matter what foods are bothering you – and how our 5R protocol is the personalized plan to get your life back.
How to Overcome Food Intolerances
As discussed earlier, food intolerances can occur with many types of foods, but lactose, histamine, and fructose are common.
No matter what foods are bothering you, your food intolerance is a signal that something in your body is not in harmony.
When your digestive health is compromised, it affects every system in your body. Even though you’re sleeping, you don’t have energy. Even though you’re eating healthy food, you’re struggling with belly pain. Even though you’re eliminating this food group or trying that supplement, your symptoms just aren’t going anywhere.
Improving gut health is the path towards reducing or eliminating your symptoms.
Our societal norms are pretty rough on your digestive system. Our foods tend to be overly processed and contain a lotta chemicals. We are praised for working 24/7, not sleeping enough, and conquering HIIT workouts every day. All of these habits wreak havoc on our digestive tract and make it so much harder for our bodies to tolerate regular food.
As clinical nutritionists, we take a careful and thorough approach to truly understand all of the factors that have contributed to where you are (and how you feel) today. This enables us to find the right approach to offer you lasting relief. Our approach includes:
- Review your health history to understand root causes and health conditions
- Review your current medications with an eye for medications that disrupt digestive health (lookin’ at you, birth control).
- Recommend a therapeutic diet that is tailored to your preferences and lifestyle to help manage your symptoms and address nutrient deficiencies
- Make a plan to reduce stress and prioritize sleep
- Guide you through systematic food reintroduction and determine if any food sensitivities remain
- Support you throughout your whole journey
The good news is that we can help you uncover the root causes of your digestive issues, work on a concrete plan to make progress, and celebrate with you as you have fewer symptoms (and are able to enjoy a wider variety of foods – wahoo!).
Key Takeaways
Digestive health is so dang important, but most doctors are not talking about it with their clients (nor are they equipped to help their clients to take clear action).
As clinical nutritionists: we’ve got your back. Well, your back and your gut health.
It takes a comprehensive look at your health history to make a plan for the future that actually works. Trying this elimination diet or that supplement is like throwing spaghetti on the wall and seeing what sticks.
Schedule a discovery call today to launch your journey to lasting symptom relief.
