Problems with digestion occur more often with aging. Digestive disorders affect 62 million Americans and are one of the nation's most serious health problems leading to over 48 million ambulatory care visits annually.
Many bodily functions, including the digestive tract, slow down as we age. This leads to an increase in digestive complaints and comorbid conditions. Luckily for us, a functional medicine approach narrows down the root cause of many of these digestive complaints and can help personalize an effective treatment strategy to reduce symptoms and increase digestive health.
8 Common Digestive Issues That Happen As We Age
Constipation is one of the most common digestive issues of the elderly, and the prevalence increases as one ages. Constipation can be caused by many factors and can be divided into primary and secondary constipation. (6-10)
"Functional," idiopathic," and "primary" constipation are terms used to clarify that one's main medical problem is constipation itself rather than a symptom of another underlying condition. Examples of primary constipation include normal transit constipation, slow transit constipation, and outlet constipation (a blockage).
Secondary constipation occurs due to an underlying health issue or a side effect of a medication.
Causes of Constipation
- Functional constipation
- Anatomic causes
- Abnormal musculature of the gut
- Nerve dysfunction
- Pelvic floor dysfunction
- Medications (such as laxative abuse and prescription medications)
- Metabolic and endocrine causes (such as low electrolytes, hypothyroidism (low thyroid), diabetes mellitus (DM), or kidney disease
- Immune-mediated causes (i.e., celiac disease, food allergies, food sensitivities, etc.)
- Poor dietary habits, including a low-fiber diet
- Low fluid intake
- Caffeine abuse
- Overuse of alcohol
- Medications (such as laxative abuse and prescription medications)
- Psychological issues (emotional)
- Lack of activity
In general, it is common for the digestive tract muscles to slow down with age. Slower digestion also tends to be more predominant in the elderly with chewing disorders, reduced physical activity, and who are frail. (14-16) Transit time (the passage of stool after one consumes food) is likely prolonged in the stomach and the colon, not the small intestine.
Causes of Slower Digestion
Possible causes of motility impairment in older adults include:
- Impaired smooth muscle contraction and relaxation in the digestion tract
- Alterations in the gut's nervous system (enteric nerves or specialized nerve cells)
- Aging cells in the gut lining which secrete enzymes related to digestion and motility (e.g., cholecystokinin, leptin, ghrelin, insulin, and peptide YY)
Lower Stomach Acid
The stomach secretes hydrochloric acid (HCL) to aid in the digestion of protein and absorption of nutrients.
It is often believed that as one ages, their secretion of HCL decreases; however, this may not be the case. One review found that stomach acid secretion was either unaffected or increased in the elderly; however, the risk factors and conditions associated with lower HCL were higher. These include H. pylori infection and atrophic gastritis.
Risk Factors for Lower Stomach Acid
Along with age, the following are risk factors for lowered stomach acid secretion:
- Vitamin deficiencies (iron, zinc, and B vitamins)
- Medications (antacids, etc.)
- Helicobacter pylori (H. Pylori) infection
- Stomach surgery
Lower Digestive Enzyme Production
Pepsin, a stomach enzyme that helps with protein digestion, declines after 70 years of age. Furthermore, studies show that subjects above 65 years of age had significantly reduced bicarbonate and enzyme (lipase, chymotrypsin, amylase) secretions. Lack of these enzymes can lead to malnutrition, compromised digestion, and other health consequences.
It's common for adults to have occasional heartburn. But, as we get older, it can become more frequent.
Risk factors for Heartburn
- Excessive weight
- Reduced pressure to open the lower esophageal sphincter (a valve between the esophagus and stomach)
- Impaired motility
- Hiatal hernia (60% of people over 60 have a hiatal hernia)
- Decreased saliva volume and bicarbonate concentration
The elderly are more at risk for colon polyps (small growths in the colon). Polyps are often painless and found routinely with screening. Nearly all colorectal cancers are thought to arise from adenomatous polyps, but this progression is often prevented with the proper removal and regular colonoscopies. (25-27)
Although there is no consensus on the underlying causes of increased polyps in aging, it may be related to age-related changes fueled by lifestyle factors. The cells in the gastrointestinal tract lining are in a state of rapid renewal and turnover throughout the lifespan. In aging, there is likely an accumulation of cells in the GI tract with an imbalance in the breakdown. This occurs along with an altered mucosal immune response in the gut lining.
Ulcers, or perforations in the stomach that bleed, are more common in the elderly.
Risk Factors for Ulcers (16, 28-30)
- Reduction of the acid protective effects of neutralizing compounds and prostaglandins levels (anti-inflammatory compounds made by tissues) in the stomach (gastric) mucosa
- Increased prevalence of Helicobacter pylori infection
- Changes in gastrointestinal motility
- Altering gastrointestinal hormones
- Immune disorders
- Psychological and social characteristics
- Increased use of NSAIDs
The microbiota found in our digestive tract can become imbalanced by various environmental, dietary, and lifestyle factors, complicating digestive disorders.
Our gut microbes play an essential role in the digestion of food, production of nutrients, synthesizing vitamins, metabolizing drugs, detoxifying toxins, stimulating gut lining cell renewal, and activating and supporting the immune system. All of these processes can be affected by aging.
For example, the ratio of microbiota in the elderly has been shown to correlate with measures of frailty, co-morbidity, nutritional status, and inflammation. There is also evidence of less short-chain fatty acid production and changes in digestive capacity in the colon as a result of these alterations. Furthermore, opportunistic, pro-inflammatory bacteria increase with advancing age.
Interestingly, a lower colonic fermentation has also been observed in older women vs. younger women. This could also relate to the changes that occur with sex hormones in menopause with age and its impact on the gut microbiome.
Functional Medicine Labs to Help Protect Your Digestive Health as You Age
Conventional labs and imaging should complement functional measures to rule out possible pathologies. Medications should also be assessed for their contribution to constipation and other digestive complaints.
A complete blood chemistry and differential with HbA1c (hemoglobin A1c) should be done to assess for infections, diabetes, and blood sugar issues which are prevalent in the elderly. These contribute to digestive problems and malabsorption.
Imaging for Lower Colon Abnormalities
- Measurements for transit time
Testing for Ulcers and GERD
- An upper GI endoscopy
- Ambulatory acid PH probe test (to test for stomach acid)
- Imaging for the esophagus
Testing for Slower Transit
- A comprehensive thyroid panel is often done in the elderly to rule out hypothyroidism as a secondary cause of constipation.
- Assessing for dysbiosis and digestive health is imperative to establish a healthy microbiome that can foster a balanced digestive tract. Comprehensive stool tests offer a complete look at gut health by measuring pathogens and analyzing digestion, nutrient absorption, inflammation, and immune function (including celiac markers), all of which impact digestive health.
- A SIBO test, H.pylori, and additional pathogens (infectious markers) can also be considered to assess for infectious causes of GERD, ulcers, and other digestive disorders.
Functional Medicine Treatment Digestive Disorders
Proper attention to history, examination, and investigation is needed to address the root cause of constipation, as a considerable range of treatment modalities are available.
Factors contributing to constipation, altered motility, and slower transit, including medications, caffeine, alcohol, and various disorders, should be addressed first.
Many functional medicine practitioners will focus on hydration, nutrition, supplements, and movement vs. laxatives to treat functional constipation.
Dehydration is estimated to occur between 17-28% of older adults and can lead to chronic constipation. It is, therefore, essential to encourage proper hydration. Some practitioners will include electrolytes in patients' daily water intake as electrolyte imbalance can lead to muscle weakness, thus accelerating the occurrence of chronic constipation.
Water-insoluble, nonfermentable fibers increase stool bulk and decrease gut transit time. These foods may help with alleviating the symptoms of slower digestion in aging.
Water-soluble fibers dissolve in water and liquids in the GI tract. It is formed into a gel-like substance that our gut bacteria can digest.
Sources of fiber in the diet include beans, peas, and whole grains. Some fruits and vegetables are also relatively high in fiber.
Probiotics and Synbiotics
Various probiotics may be beneficial for the aging digestive tract. (50-52) Lactobacillus delbrueckii subsp. Bulgaricus may support overall digestive health, and Lactobacillus casei/paracasei have been shown to be helpful in patients with constipation.
One randomized study with 100 patients with slow transit constipation found that those taking a synbiotic (a combination of prebiotics and probiotics) had a 64.6% clinical improvement. During the 12-week intervention, those on the synbiotic reported increased stool frequency, improved stool consistency, decreased colon transit time, and improved constipation-related symptoms.
Physical activity can help to enhance bowel regularity. Exercising increases bowel transit time in the large intestine, improving the overall efficiency of the digestive tract. Finding various ways to move throughout the day and boosting one's physical activity should be done safely with one's physician if they are not very mobile.
Digestive Enzyme Support
HCL and digestive enzymatic support may be chosen to be initiated by clinicians based on findings from one's diagnostic results. Addressing the root cause of lower HCL and enzymes is important to offer the best treatment. Medications and other lifestyle factors such as stress, alcohol, and caffeine can contribute to issues with these digestive secretions and should be reduced or eliminated if possible. After addressing the root cause, supplementing with digestive enzymes and HCL can help patients with better digestive support and alleviate many digestive complaints including heartburn, constipation, and slow transit.
Nutrients such as iron, zinc, and B vitamins are essential to produce stomach acid and should be supplemented if low.
H. Pylori Treatment
H. Pylori is commonly treated with either antibiotics or herbal and supplemental antibacterials as well as increasing probiotics to drive out the overgrowth of harmful bacteria.
Mastic gum & Licorice Root
Mastic gum and Licorice root both have promising studies for decreasing the colonization of H.pylori. Both of these supplements are commonly used by functional medicine practitioners to reduce H.pylori. Practitioners should test for H-pylori after treatment to confirm eradication.
In a review of 33 clinical studies, probiotics supplements were found to influence H. pylori colonization compared to control groups. The subgroup analysis confirmed four individual strains to be the most effective. These include:
- Lactobacillus acidophilus
- Lactobacillus casei DN-114001
- Lactobacillus gasseri
- Bifidobacterium infantis 2036
Certain foods may aggravate GERD and may initially need to be avoided until the root cause is addressed. These include alcohol, high-fat foods, chocolate, alcohol, mint, acidic foods, and caffeine.
Herbs and Supplements
Demulcents herbs that soothe irritated tissue of the stomach and intestine, including licorice and slippery elm, may also be used to calm intestine irritation in GERD and ulcers. Melatonin has shown success in various human trials for a healthy stomach and digestive tract lining, as well as other digestive issues.
Suspicious polyps should be removed surgically when found to prevent cancer growth. Considering polyps may have genetic and environmental components not yet identified, following lifestyle factors to promote a healthy microbiome can be helpful.
The following will assist in building and maintaining a healthy microbiome that supports a robust digestive system. These actions can be implemented throughout the lifespan.
Fermented foods, such as yogurt, kefir, kimchi, tempeh, and sauerkraut, contain microbes that can support a healthy microbiome. (Those with histamine issues should be cautious.)
High-fiber foods, including whole grains, fruits, vegetables, nuts, and seeds, contain prebiotics which are good for feeding helpful bacteria and help to produce short-chain fatty acids that support digestive and immune health.
Sleep, stress reduction, and exercise all have been found to positively impact the gut microbiota.
More and more researchers and physicians are realizing that we need to consider the home of these trillions of tiny microbes in our bellies to have a fighting chance of avoiding disease progression that affects all our organ systems as we advance in years.
By exploring the root causes of some common digestive issues that occur with aging, implementing the proper diagnostics, and incorporating dietary, lifestyle, herbal remedies, and supplements, we can address the contributors to them to keep ourselves "young at gut."
Lab Tests in This Article
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