The old saying is true: you are what you eat. Fortunately, we’re all becoming increasingly aware of how our diets impact our overall health.
If you’ve started to notice a pattern of digestive discomfort, or something far worse, it may be time to determine if you have a health condition that relates to your diet. You could also have an underlying allergy that is triggered by certain foods.
The more you know, the easier it is to protect yourself. This article will help inform you about the most common dietary diseases, afflictions, and allergies, including:
The symptoms of serious diseases like Crohn’s, Type 2 diabetes, and Celiac disease
Common food allergies
Food choices that could lead to some health problems, such as hypertension
How to get a diagnosis allergies and food intolerances
Ingredients and foods to avoid for different conditions
We will equip you with all of the information you need to read labels properly and manage your health. We’ll also show you how to spot common symptoms of serious ailments or not-so-serious, mild food intolerances.
Many of the illnesses below can be caused by genetics, but they are often related to an unhealthy lifestyle or a lack of knowledge when it comes to diet.
374 million people are at increased risk of developing type 2 diabetes.
With Type 2 diabetes, your body’s cells stop responding normally to insulin. This is also called “insulin resistance”. Your pancreas essentially makes up for insulin resistant cells by making more insulin. Eventually, your pancreas can’t keep up, your blood sugar levels rise and potentially damage a number of organs including your heart, eyes, and kidneys.
Type 2 diabetes remains one of the largest health concerns around the world. Unlike Type 1, Type 2 diabetes is not a genetic disorder, although some people diagnosed with Type 2 do have a genetic predisposition. There are also individuals with otherwise healthy lifestyles who develop Type 2 after age 45.
However, throughout the 1990s and 2000s, more young people were exposed to processed foods high in refined carbs (like sugar) and Type 2 diabetes became a much larger health problem. As such, Type 2 is associated with diets that are higher in refined sugars, carbohydrates, and fats (fast foods, convenience foods, sugary sodas, and snacks).
Once you have Type 2 diabetes, it can be managed, but it’s a very dangerous disease. No one wants to live with the constant threat of cardiac arrest, blindness, kidney damage, high blood pressure, and more.
Please make a note that by the time Type 2 diabetes symptoms emerge, your body may already be experiencing severe neural and organ damage.
The most common symptoms of Type 2 diabetes are:
Frequent, extreme urination
Numbing of the extremities, especially hands and feet
Constant and almost insatiable thirst and increased hunger
Increased infections and wounds that don’t heal
Blurred or impaired vision
Sudden weight loss
Before it gets that far, make sure you’re managing the conditions that can lead to Type 2 diabetes including:
High blood pressure
High levels of triglycerides and LDL (or “bad”) cholesterol
Morbid obesity along with physical inactivity
A history of heart or cardiovascular disease
If you fall into any of those health categories, an immediate family member has been diagnosed with Type 2 diabetes, or you experience any of the symptoms, contact your doctor immediately.
Visit your primary care provider for an annual physical exam with blood testing. Your annual visit will also monitor your cholesterol levels, blood pressure, weight, and lifestyle issues.
Cases of Type 2 diabetes spiked in the late 20th and early 21st century with the rise of convenience and fast foods. Frozen, processed, and instant foods are high in saturated fats and processed carbohydrates – it’s what makes them taste good.
Soft drinks and sodas are all full of simple sugars that lead to the kind of weight gain and imbalances that cause both obesity and Type 2 diabetes. It’s not just processed sugars. Keep in mind that fruit juices are all high in the very kind of sugars that, if overly consumed, can become a problem.
Here’s a general rule of thumb:
If a food is extremely high in carbohydrates, most of those carbohydrates should come from the fiber content. So, foods made from enriched, processed white flour (breads, sugary cereals, baked goods, etc.) should be avoided.
Instead, foods with whole grains (whole wheat flour, brown rice, barley, quinoa, etc.) and foods with high fiber content (legumes, single servings of fresh fruit, nearly every vegetable you can name) balance your appetite and keep you from snacking all day.
You can also look for specialized meal services that cater to people with diabetes.
Heart disease is the #1 most common killer in the world. In 2019, it was the #1 cause of death globally and the most common cause of death in the U.S. even with COVID raging (cancer remains #2).
As with almost every disease, of course genetics plays a factor. However, in this case, doctors and scientists are learning that lifestyle and diet are leading causes of heart disorders. Keep in mind that ‘heart disease’ is a general category that includes a number of cardiovascular-related illnesses and conditions.
There are both congenital (from birth) heart conditions and diseases that are related to lifestyle. Congenital heart defects include defective valves and require surgical intervention. However, in this guide, we will cover symptoms and causes of coronary artery disease which are linked to a poor diet high in saturated fats, sodium, and inactivity.
Coronary artery disease, also called atherosclerosis, is caused by a build-up of fatty plaques in your arteries. The build-up restricts healthy blood flow to the heart and can also lead to blood clots. That combination could lead to strokes, heart attacks, severe chest pain, or irregular heart beats.
It’s extremely important to contact your doctor or visit an emergency room if you have any symptoms listed below. Atherosclerosis often goes undiagnosed until the patient suffers a major cardiac event or a stroke. A number of other health conditions can contribute to coronary artery disease including:
A diet high in saturated fats, sodium, refined carbohydrates (sugars)
High levels of cholesterol
High blood pressure
Lack of exercise
Discomfort and pain in the chest
Severe pain in the jaw, upper abdomen, or back
Numbing and pain in legs and arms
If you are concerned that you may be a candidate for coronary heart disease or you’re experiencing any symptoms, it’s critical that you visit a doctor immediately. The diagnostic process includes a variety of imaging and testing like:
A painless test that records the signals in your heart in order to spot abnormal heart rhythms.
A device you wear on your chest for a minimum of 24 hours to log your heart’s activity.
An imaging machine, similar to an ultrasound, that uses sound to show your heart’s beat and blood flow.
A test that involves raising your heart rate (usually on a treadmill) to monitor how it responds to activity.
A diagnostic surgical procedure where a microscopic camera is inserted through the arm, leg or groin. Ingested contrast dye is combined with an x-ray machine to observe the full blood flow through the heart.
CT Scans and MRIs
If your doctor is concerned about a structural problem, you may require advanced imaging with an MRI or a CT scan.
High blood pressure is one of the leading causes of heart disease and cardiovascular disease. It’s also related to heart attacks and strokes. Keeping it under control is one of the most important aspects of staying healthy and avoiding cardiac incidents and other health problems as we age.
The most common, or potentially life-shortening impacts of high blood pressure are:
Hardening of the arteries (atherosclerosis)
Loss of vision
Severe swelling in the extremities (adema)
Blood pressure measures the force of your blood pushing on your blood vessel walls. It’s measured in two numbers: systolic blood pressure and diastolic blood pressure. Systolic measures the pressure in your arteries while your heart is beating, and diastolic measures the pressure in your arteries when your heart is resting in between beats. A healthy heart rate is considered somewhere in the range of 120/80.
The only way to know definitively if you have high blood pressure is to have it tested by a physician. If you know you have high blood pressure, it’s easy and wise to invest in a blood pressure cuff for home use.
High blood pressure can be caused by a number of issues, including genetics. However, the #1 cause of high blood pressure in the diet is sodium. So avoid processed foods, especially frozen, convenience (or fast) food, and canned foods.
Cholesterol is a semi-solid substance found in your blood that your body uses to repair cells. If you have too much of it, you can develop deposits in the blood vessels. Those deposits may lead to blockages which could cause hypertension, strokes, heart attacks, and cardiovascular disease.
Your body creates two types of cholesterol, high-density lipoprotein (HDL) and low-density lipoprotein (LDL). HDL actually removes fats from the blood, which is why it’s often referred to as “good” cholesterol. The measure that doctors pay attention to is your LDL level. When that gets high, a physician may opt to put you on medications or recommend lifestyle changes.
High LDL (or “bad”) cholesterol can be inherited or genetic, but it’s often the result of a poor diet and lack of sufficient exercise.
LDL Levels in mg/dl*
*(milligrams per decimeter of blood)
Slightly High/Above Normal
Like hypertension, high LDL cholesterol doesn’t come with a list of symptoms. Rather, it often causes other critical health problems. If not detected early, patients often discover they have high cholesterol after being admitted to the hospital for an issue like a stroke or a heart attack.
You need to get tested annually from a physician to monitor your LDL and HDL levels.
Celiac disease is a genetic autoimmune disorder. While it often goes undiagnosed in both children and adults, it is a disease you inherit (or are born with). Someone with celiac disease cannot digest a protein found in many grains (including wheat) called gluten.
Autoimmune diseases are called such because the body’s natural immunity misreads a process in the body. When individuals who suffer from celiac digest any ingredient that contains gluten (found in wheat, barley, and rye) their immune system essentially misfires. Instead of digesting the gluten in a healthy way, the immune system attacks the small intestine.
When this happens over a long period of time, the lining of the small intestine (called the villi) becomes damaged. The worse the damage, the harder it is for the small intestine to digest nutrients. The resulting malnutrition can cause life altering and threatening complications.
Celiac disease may develop at any age, but typically starts in childhood. Because it’s relatively rare, it often is misunderstood or misread in both children and young adults. When left untreated or ignored, celiac can lead to life-altering conditions and nerve damage. Those include:
Multiple sclerosis (MS)
Type 1 diabetes
Coronary artery disease
Skin conditions like dermatitis
The sooner the diagnosis, the less likely the patient is to suffer a second autoimmune or health condition.
Celiac disease symptoms manifest slightly differently in adults and younger children.
Chronic diarrhea, bloating, and abdominal pain
Unusually pale, foul-smelling stool
Severe weight loss
Lethargy and fatigue
Unexplainable mood swings and behavioral issues
Teeth defects and enamel issues
Shorter stature or delayed growth
ADHD and a general lack of social engagement
Unexplained anemia (especially in men)
Bone and joint soreness or pain
Chronic fatigue and brain fog
Depression and anxiety
Osteoporosis and bone loss
Liver disorders (fatty liver, transaminitis, etc.)
Numbness, pain, and tingling in the extremities (peripheral neuropathy)
Infertility and recurrent miscarriages
Chronic missed or skipped menstrual cycles
Consult with a physician to determine if you have celiac disease. A gastroenterologist or GI specialist will analyze blood samples to look for specific antibodies that indicate a negative gluten reaction. In some cases, an intestinal biopsy may be performed.
Reactions to a wheat allergy range from a mild intolerance (like seasonal hay fever) to immediately life-threatening reactions.
An allergy is an autoimmune response where the body releases high amounts of histamines to isolate a substance the body can’t process (it’s why you sneeze and cough when you have a cold, for example). While not everyone has allergies, they are extremely common. A wheat allergy is like an allergy to cats, pollen, or peanuts – exposure typically causes a fast and immediate reaction.
Someone with a wheat allergy will experience mild to severe reactions when they ingest any food containing wheat like breads, pasta, alcohol, etc. Similar to other allergies, reactions range from the mild (sneezing, itchy, watery eyes) to severe (anaphylaxis, hives, fainting).
Throat swelling and irritation
Hives, skin rashes
Nasal congestion and sneezing
Severe digestive issues including cramps, nausea, diarrhea, vomiting
*Anaphylaxis is life-threatening and should be treated as a medical emergency. Symptoms of anaphylaxis include:
Severe difficulty breathing/blocked air passageways
Severe hives and swelling
Pale or blue skin
Inability to swallow
Fainting and severe dizziness
Avoid the same foods as anyone suffering from celiac disease.
Gluten intolerance impacts people who have a mild and inconvenient reaction to gluten.
Unlike celiac disease, an intolerance causes discomfort and does have some side effects, but it typically does not cause any long-term health issues. It’s also called non-celiac gluten sensitivity and there remain challenges for doctors to provide a conclusive diagnosis.
Gluten intolerance or sensitivity simply means that some people have a harder time digesting or breaking down gluten than others. It’s estimated that as many as 6% of the population suffers from some form of gluten intolerance. While some mild allergy symptoms (like a sore or itchy throat and mild headache) accompany gluten intolerance, mild digestive discomfort is more common.
It’s worth noting that a little bit of bloating after you eat isn’t necessarily unhealthy or worrisome. When you break down sucrose (the main ingredient in dietary fiber) your body naturally produces a bit of gas. So eating high-fiber breads, grains, and foods like legumes produces a perfectly natural and healthy reaction.
Gluten intolerance comes with a list of slightly more problematic digestive and intestinal distress. Constipation, diarrhea, and stomach cramps, for example, are very common complaints.
Brain fog and memory issues
There is no concurrence among the medical community for how to diagnose a gluten intolerance. The medical community has only recently started to recognize the verifiable existence of gluten sensitivity. As such, you have to monitor your own diet and discuss your symptoms with your doctor.
As with any health condition, see a doctor as soon as you notice recurring health issues. Any of those symptoms could also be related to a larger health issue or digestive disorder.
Avoid the same foods as anyone suffering from celiac disease or a wheat allergy.
If you live with gluten intolerance, try out gluten-free meal kits and delivery services to ensure you won’t experience any negative side effects.
Gastroesophageal Reflux Disease (GERD) is the medical definition of acid reflux. Occasionally, digestive acids from the stomach flow back up into the esophagus and cause minor irritation. It’s fairly common and happens to most people without any serious consequences.
You could experience acid reflux or GERD when you eat highly acidic or fatty foods. Many people experience GERD when they’re under a lot of stress. If it’s occasional and moderate, you can treat it with over-the-counter or prescription antacids. When it becomes chronic, you may need more serious medical intervention.
Severe GERD can cause permanent esophageal damage or could be a sign of something worse, like a hiatal hernia.
Risk factors and habits that can cause GERD include:
Eating large meals late at night
A diet heavy in fatty or fried foods
Beverages that cause irritation like alcohol, coffee, and carbonated sodas
Doctors often look for a hiatal hernia when a patient complains of severe or chronic acid reflux. A hiatal hernia happens when the stomach breaches an opening in the diaphragm and bulges into your chest. Doctors often don’t know what causes hiatal hernias, but they require surgical intervention.
To diagnose a hiatal hernia, your doctor will perform an endoscopy (sending a camera into the stomach through the esophagus), an x-ray with barium dye, or an esophageal manometry (a surgical diagnostic procedure that tests the strength of your esophagus when you swallow).
Burning sensation in the chest or chest pain
Slight regurgitation of food or drink
Sensation of a lump in the throat
Interrupted sleep (from heartburn)
If you are taking antacids more than 1-2 times weekly, it’s time to see your doctor. Your physician may request that you undergo a range of diagnostic procedures to further measure your condition including:
A pH probe test (a non-invasive surgical process that measures the acid levels in your esophagus)
Lactose is a simple carbohydrate (sugar in its rawest form) and it’s found in a number of different foods. Diary foods, like milk, cream, and ice cream, have very high concentrations of lactose.
Your body produces an enzyme called lactase which breaks down lactose once it’s in your small intestine. People with too little lactase experience mild to more severe inability to break down and digest lactose.
A lactase imbalance can also be temporary.
For example, if someone has recently suffered from a stomach or digestive flu, infection, or food poisoning, it may take a few weeks or even months for the body to fully recover its proper balance of intestinal flora, which includes lactase. Lactose intolerance is also a common side effect of some forms of cancer treatment.
As children, because we get most of our nutrition from milk, we produce more lactase. When most adults age, lactose intolerance can become more common.
Some people have a lifelong intolerance to lactose which results in a range of mild, uncomfortable, and inconvenient symptoms. There are also genetic predispositions, especially among ethnic people of African, Asian, Hispanic, or Native American descent.
Over-the-counter lactase enzymes when taken orally prior to eating can often counter the impact of lactose intolerance.
Intestinal cramps, gas, bloating
If you’re concerned that you have a lactase imbalance or a lactose intolerance, consult your doctor. A stool or blood sample can often detect a shortage of lactase in the intestines. It’s especially important to speak to a doctor if you are concerned about getting an adequate amount of calcium in your diet.
A nut allergy is present when a person’s body does not have the capacity to break down proteins found in certain types of nuts. An allergic reaction to nuts is dangerous and can be fatal. It is a genetic condition that typically manifests in early childhood.
Many people are so sensitive that exposure to a small amount of dust from nuts could send them to the hospital. That’s why, for example, most airlines have stopped handing out peanuts or tree nuts on flights.
Nut allergy sufferers also have to be aware of products that are processed in the same facilities as nuts. Because the reaction to nuts can result in complete anaphylaxis, it’s recommended that sufferers carry an epinephrine, or “epi”, treatment with them at all times. The single-use shot administers a quick shot of medication that keeps the airwaves open until the patient can seek medical attention.
People who are allergic to peanuts are often also allergic to tree nuts, but not always. If you start having symptoms from one, see a doctor immediately to confirm the source of your allergy.
Tingling in your mouth and throat
Tightness in the throat and chest
Nausea or vomiting
Stomach cramping and pain
A doctor or an allergist can confirm whether or not you have a nut allergy.
Like nut allergies, shellfish allergies are often dangerous and very easy to spot. The moment you notice any kind of reaction to shellfish like shrimp, scallops, crab, lobster, oysters, or clams, get to a doctor.
Shellfish allergies can often show up later in life and may get more serious and dangerous with time.
Some marine life contains proteins that are common amongst crustaceans and mollusks. When the body can’t break down those proteins, your immune system releases histamine. The reactions can range from mild to quite serious. The symptoms show up anywhere from minutes to one or two hours after eating.
Tingling in the lips and throat
Hives and swollen eyes
Vomiting, diarrhea, stomach cramps
See your doctor to discuss your symptoms.
Also, just because you’re allergic to one type of shellfish does not mean you’re allergic to all shellfish. For example, if you have a crustacean allergy, you may be able to eat mollusks safely. Also, your allergy could be confined to just one type of shellfish. All of this information should be confirmed with a licensed specialist or doctor.
Crohn’s is an autoimmune disorder that is also classified as an inflammatory bowel disease. The body’s immune system attacks different parts of the digestive tract depending on the type of Crohn’s the patient has. It is a genetic disorder and is inherited at birth. Diagnosis can happen in early childhood, but Crohn’s often doesn’t manifest until teen years or early adulthood.
Crohn’s can go into a remission period, and return periodically causing painful and difficult-to-manage flare ups that may require hospitalization and major medical intervention.
Every subtype of the disease has a range of painful and challenging symptoms. The most common symptoms are related to digestive issues including severe diarrhea, abdominal pain, weight loss, and malnutrition.
Local Crohn’s impacts the digestive tract. Systemic Crohn’s refers to the group of issues that impact organs outside the intestines and bowel. Systemic Crohn’s causes a range of serious conditions throughout the body, some of which are listed below.
Crohn’s often causes the body to attack its own connective tissue (similar to rheumatoid arthritis). Crohn’s-related arthritis conditions include peripheral arthritis, which impacts joints and soft tissue throughout the body including the ankles, hips, knees, elbows, and wrists.
Axial arthritis related to Crohn’s impacts the lower back. In rare cases, another form of spinal arthritis called ankylosing spondylitis could lead to severe inflammation in the spine, and can spread to the eyes, heart, and lungs.
Irritation and inflammation of tissues surrounding the bile ducts.
In some cases, Crohn’s sufferers also have to manage chronic kidney stones.
Crohn’s complications can also cause:
Urinary tract issues
Mouth ulcers and skin infections
Fistulas (ulcerated sores that develop in the intestines and surrounding organs)
Lower bone density
Bacterial imbalances in the digestive tract
Severe abdominal pain
Chronic and unmanageable diarrhea
Delayed growth (in children)
Joint pain and swelling not related to injury
Bruising, hair loss, skin lesions
Rectal bleeding/pain with bowel movements
Getting a definitive diagnosis for Crohn’s could require a range of imaging and non-invasive surgical diagnostic procedures. It’s likely that a patient will need a combination of several different tests to get a conclusive Crohn’s diagnosis. That may also involve seeing various specialists including a rheumatologist, gastroenterologist, general doctor, endocrinologist, and potentially specialty surgeons (colo-rectal, etc.).
Barium-guided and contrast x-rays
Endoscopic procedures like sigmoidoscopy
Full blood workup
Irritable Bowel Syndrome (IBS) is a very common gastrointestinal disorder associated with difficulty digesting food and passing waste. The most common symptoms occur after eating or during a bowel movement. IBS is more properly called a “classification of symptoms” rather than an illness or a disease. However, it can be diagnosed and, with proper management, may even go away.
There’s no conclusive evidence for the causes of IBS. IBS can be temporary and treated without drugs or medical intervention. Lifestyle changes and reducing stress are often adequate to manage the condition.
Bloating and pain after eating
Diarrhea or intestinal discomfort
Mucus in the stool
Loss of appetite
IBS isn’t classified as a disease.
Doctors may give you a series of tests to rule out other health conditions (including Crohn’s, celiac disease, food intolerances, and other digestive disorders). If the symptoms persist after establishing the patient doesn’t have an underlying condition, the doctor will likely discuss lifestyle and diet adjustments to manage IBS.
Egg and milk are amongst the most common allergies in children. If the body has an inability to break down the proteins found in eggs or milk, the immune system will essentially over-react with a histamine response. Like nut allergies, that response can range from mild to more severe. As children get older, it’s also common that their digestive system matures and they literally outgrow the allergy.
Itchy skin rashes
Sneezing, watery eyes, and nasal congestion after consumption
Difficulty breathing including wheezing, coughing, asthma attacks
Diagnosis of an egg or dairy allergy is completed by a physician. Patients may get a blood panel to verify if certain antibodies are present. A skin prick test may also be performed. A microscopic sample of the allergen is pricked into the skin with a small needle. An itchy, red bump on the skin confirms an allergic reaction.
Your doctor may also recommend an elimination diet to see how the body responds.
The term elimination diet may be misleading. The purpose of an elimination diet is not to remove pounds from your body, but foods from your meal rotation. If you and your doctor suspect that you have an intolerance or an allergy to a single food, an elimination diet could help narrow down the culprit.
We always recommend that you partner with a physician or a licensed healthcare provider before you start any new diet or nutritional program.
An elimination diet is NOT a detox diet. Detox diets often recommend avoiding entire groups of foods, like animal products, alcohol/sugars, and certain grains at the same time. An elimination diet targets a specific set of foods or a single ingredient. The entire purpose is to determine if your symptoms improve or completely disappear when you remove that single food from your daily rotation.
An elimination diet has two stages: elimination and reintroduction.
During the elimination stage, you completely remove a single food – eggs, for example – from your diet. You also avoid any dishes or recipes that contain that single ingredient. Follow that diet for the period prescribed by your doctor. You may also be asked to keep an active journal or record your symptoms during that time.
You then slowly reintroduce foods back into your diet and make note of the reaction. As you reintroduce those foods, you may be able to determine if you have an allergy or just simply an intolerance. If you experience more allergy-like symptoms for a single food, you may be able to learn more from further tests.
If you have an intolerance, an elimination diet can help you understand the degree to which that food is causing you problems. Perhaps you can, for example, handle something like gluten or acidic foods in lower quantities or on rare occasions.
It can be difficult to measure the overall efficacy of elimination diets, although they’ve been popular for decades. For people who have mild intolerances, you will have to use your own judgement if your symptoms have improved or not. Ultimately, you may be the final judge.
Allergies with physical manifestations or obvious side effects could lead to a conclusive diagnosis. So, if you have an allergy to eggs or wheat, and you no longer have a skin rash or hives when you remove them from your diet, it’s almost a foregone conclusion that you have an allergy.
Even though many of the conditions we list here are complicated (and several are dangerous), you can still enjoy a dynamic and fun diet while living with any of them. Print out our helpful tips or bookmark this article so you always have it handy.
The most important advice we can offer is pretty simple: be your own advocate. No matter where you are, respectfully ask to know what the ingredients in a dish are.
Any restaurant server, host at a dinner party, or any food service should be prepared to tell you everything that’s in a dish. As long as you’re respectful and remind people that you have a serious health condition, you should get the information you need.
Read and study labels. Use your judgement. Do your homework and find a doctor who will work with you to help you live a healthy and productive life.