The Oatmeal Cure for Diabetes: A Century-Old Dietary Strategy Seeing Renewed Interest
In the early 20th century, before the discovery of insulin, diabetes was often an agonizing and swiftly fatal diagnosis. So when German physician Dr. Carl von Noorden reported extraordinary success in treating his diabetic patients with a diet centered around oatmeal and other high-fiber whole grains – essentially curing some cases – it understandably created major excitement and controversy in the medical community.
While some were skeptical, many doctors rushed to test the so-called "oatmeal cure" on their own patients, with astonishing results that saved or significantly prolonged lives. Over the next decades though, the oatmeal cure diet fell out of favor as insulin and other medical interventions took center stage in diabetes care.
But renewed scientific interest and research suggests that for some diabetics, making a simple change to eat more oats and other high-fiber grains may provide significant benefits unachievable through medication alone – perhaps even impacts on underlying disease processes if adopted consistently over the long term.
The Oatmeal Cure Diet: What Is It?
In essence, the oatmeal cure diet Dr. Carl von Noorden pioneered consists of:
- High fiber intake, particularly from whole oat grains
- Very low intake of animal protein
- Low overall fat intake, focusing on plant-based fats
So a typical daily meal plan might include:
- Oatmeal for breakfast, loaded up with oat bran and fruit
- Whole grain breads and cereals
- Lentils, beans, vegetables, fruits and nuts for other meals
- Very limited or no meat, eggs, dairy and other major animal protein sources
The fiber-rich and plant-based nature of this diet means it provides nutrients to nourish a healthy microbiome while limiting some components thought to promote inflammation. We’ll explore the science behind why it seems to work so remarkably well for diabetes a bit later.
First though, what kinds of real-world outcomes did doctors actually observe when trying it on their patients?
Remarkable Success Stories With the Oatmeal Cure Diet
Dr. Elliot P. Joslin, one of the most eminent diabetes specialists of his day, said of the oatmeal cure simply that “It works”. Though initially skeptical, he carefully studied Dr. Noorden’s reports and then experimented extensively with the diet on his own patients. For example, he placed a 35-year patient described as “a walking skeleton, just ready to die” on the oatmeal diet.
In under a week her urine sugar changed from 4.5% to just 1% , her strength and vigor returned rapidly, and she was soon back to her normal housework. Such dramatic turnarounds from near death’s door to feeling 20 years younger in just days were not uncommon.
My favorite anecdotal report is from Dr. John F. Herrick, another renowned diabetes expert at the time. When he first heard of Dr. Noorden’s published success with the oatmeal cure, he found some of the claims so incredible that he decided to implement the diet as a test.
The first patient he tried lost 40 lbs in just 45 days on the diet, with fasting blood sugar dropping from 250 down to 100 within 5 days – while he also saw the patient’s needed insulin intake decrease from over 200 units daily to just 40 units.
After witnessing such a rapid transformation, Dr. Herrick confessed with an amusing touch of overdramatic shock that “What I thought was incredible…is sober truth.” He promptly put all 10 of the diabetic patients under his hospital’s care on the oatmeal cure diet to see if results repeated!
The Key Benefits for Diabetics – And How Oatmeal Uniquely Provides Them
What is it about oatmeal that proved so beneficial? Turns out oats have a nutritional profile uniquely well suited to deliver two key factors of critical importance for diabetic health:
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Richness in soluble fiber – Oats contain one of the highest soluble fiber contents per gram of any grain. Fiber slows digestion and carbohydrate absorption from the gut, helping to blunt dangerous blood sugar spikes after meals. This smoothing effect likely drove some of the rapid improvements doctors observed in their diabetic patients’ sugar levels. Importantly for diabetics, soluble fiber from oats may also reduce cardiovascular disease risk by lowering LDL cholesterol.
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Prebiotic nourishment of a friendly microbiome – Fiber serves as an essential “prebiotic”, meaning components that selectively feed beneficial bacteria species living symbiotically in our gut microbiome. The particular polysaccharides making up oat fiber help certain populations like Bifidobacterium species grow strong. Diabetics frequently suffer from a form of gut dysbiosis characterized by low levels of these beneficial SCFA-producing bacteria.
Within 5 years the FAO predicts worldwide demand for oats will exceed available production by 4.5 million tonnes due to surging consumer recognition of their health benefits – so get your oatmeal while you can folks!
Now let’s explore some of the science behind why supporting microbial allies with prebiotic fibers like oats seems to work so remarkably well for improving metabolic health parameters like insulin sensitivity and inflammation – key drivers in diabetes progression.
How Oatmeal’s Prebiotic Effects May Influence Metabolic Processes Underlying Diabetes
Though doctors a century ago observed impressive symptomatic improvements from the oatmeal cure diet in their patients, they lacked understanding of the underlying biological mechanisms at play. But modern research is now providing those answers. Compelling evidence ties the gut microbiome to whole-body metabolic regulation in humans, including key processes involved in diabetes pathogenesis.
There appear to be three main interlinked mechanisms by which judicious prebiotic fiber sources like oatmeal beneficially modulate the gut microbiome-host metabolic axis:
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Selective increase of SCFA-producing gut bacteria – The polysaccharides in oat fiber serve as preferred “food” for certain beneficial species of bacteria. As these microbes digest oat fiber in the intestine, they create valuable byproducts like the short-chain fatty acid butyrate. Along with supplying energy for colonocytes to maintain gut barrier integrity, SCFAs reduce inflammation. Patients with metabolic diseases like diabetes frequently have low levels of butyrate & other SCFA-producing bacteria, instead harboring more proinflammatory species.
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SCFA signaling via host receptors – once produced, SCFAs get taken up into blood circulation and directly signal to the host’s cells via G-coupled FFA receptors found throughout tissues. Activation of these receptors triggers an array of responses including increasing satiety hormones from the gut, improving insulin sensitivity in adipose tissue, skeletal muscle and liver by beneficially altering lipid metabolism and gene expression, suppressing inflammation through epigenetic effects on immune cells, and more.
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Increasing glucagon-like peptide secretion – another beneficial effect of SCFAs includes stimulating L-cells scattered along the intestines to secrete GLP-1 – an incretin hormone acting at multiple sites to lower blood glucose. Via mechanisms like enhancing glucose-stimulated insulin secretion from pancreatic beta cells, slowing gastric emptying, and reducing food intake, GLP-1 helps diminish dangerous postprandial spikes.
Through these interlinked downstream effects, judicious selection of prebiotic fiber-rich whole food sources like oats appears to have the potential to drive community-level shifts that improve systemic metabolic regulation and reduce inflammation. In other words, like factoring morality into the decisions of nations shapes what flows downstream, oatmeal influences populations of micro-allies within your gut for overall better metabolic outcomes. Okay, I still can’t resist going for the grandiose metaphors!
This also highlights how depletion of prebiotic fibers in modern processed food diets leads to starvation of key beneficial bacteria. If the morality of our microbiome falls fallow, metabolic virulence reigns. Continuing the metaphorical theme, it seems less ancient Athens and more fascist dictatorship!
Okay okay, I apologize for belaboring that analogy into the ground. But the point remains – strategic “voting” with prebiotic food choices like oatmeal has potential for effecting systemic change!
Early Research Hints At Lasting Metabolic Impacts From Short-Term Diet Change
Here is where things get really fascinating. In one revealing study, insulin resistant subjects showed a 36-42% improvement in insulin stimulated glucose uptake after just a 48-hour dietary intervention with added oatmeal. And in another trial, adding oat bran to meals for just 2 days decreased daily insulin needs by close to 40% in patients with type 2 diabetes. The enhanced glycemic control persisted weeks after stopping the oat bran!
Such findings raise the exciting possibility that even brief “spike” exposures to fermentable fibers like oats could drive sudden microbiome shifts able to “lock in” positive changes. Certainly more research is still needed. But it suggests judicious short-term use of prebiotic dietary additions could help “re-set” metabolic trajectories in a longlasting way without needing overnight wholesale dietary overhauls. This is great news for those struggling to make sweeping lifestyle changes stick.
Oats delivery specialized metabolites called avenanthramides that possess anti-inflammatory, antioxidant and anti-itch bioactivities. More obscure perhaps, but no less important – the mineral manganese acts as a cofactor for key enzymes involved in carbohydrate metabolism.
Beyond fiber and plant protein content, the phytochemical and micronutrient makeup of oats also likely contribute benefits. For example, oats uniquely contain specialized polyphenol metabolites called avenanthramides. Avenanthramides have shown potent anti-inflammatory, antioxidant, and anti-itch effects in skin through suppressing histamine release. And the mineral manganese – abundant in whole oats – acts an essential cofactor for critical carbohydrate metabolism enzymes instances isocitrate dehydrogenase and glutamine synthetase.
So in many ways, oats provide a botanical arsenal targeting mechanisms underlying diabetes on multiple fronts!
The Bigger Picture: Interactions with Branched Chain Amino Acids
Now to discuss another piece of the puzzle regarding oatmeal’s benefits. Diets high in meat and other animal protein sources deliver excessive amounts of the essential branched-chain amino acids (BCAAs) isoleucine, leucine and valine. Though required nutrients for tissue growth and repair, high intakes of BCAAs from heavy animal protein consumption appear to contribute to insulin resistance and diabetes based on large population studies.
Exact mechanisms linking excess circulating BCAAs to metabolic impairment are complex and multifactorial. But factors likely involve a signaling role for BCAAs in integrating protein and glucose metabolism between tissues. For example, enhancing insulin-mediated glucose uptake into muscle while suppressing liver glucose production.
So beyond benefits from added prebiotic fiber, lowering intake of animal proteins providing excessive BCAAs – as emphasized by traditional oatmeal cure diets – also likely matters. This notion is supported by data clearly linking higher prevalence of diabetes and insulin resistance biomarkers among global populations with higher dietary ratios of animal meat versus plant protein.
Replacing refined grain calories with whole grain oats better balances this ratio, increasing intake of BCAA-poor plant protein sources. Given the skyrocketing rates of prediabetes and type 2 diabetes over recent decades, limiting meat consumption to reduce excessive dietary BCAA intake indeed seems prudent.
But animal proteins come packaged with a host of other bioactives like Neu5Gc, carnitine, TMAO precursors that promote inflammation. So whole grains like oats still win out! However, those looking to maximize benefits should also consider adding in small amounts of fermented soy products. Regular soy intake associates with markedly lower diabetes risk in Asian populations, providing all essential amino acids without excessive BCAA fractions.
As a clinical dietitian, I frequently suggest clients struggling with metabolic issues like obesity or high blood sugars try substituting one daily serving of meat with a 1/2 cup portion of tempeh or natto over a 1-2 month period. The fiber and fermentation metabolites from the soy prove powerfully prebiotic as well!
In Conclusion: A Compelling Case for “Prescribing” More Whole Oats
Though more research is still needed on details like optimal “dosing” and timing, the traditional oatmeal cure diet has a sound physiological basis for providing real benefits applicable today for many dealing with insulin resistance, prediabetes or obesity. It likely works through a combination of:
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Added fermentable fiber serving as prebiotic nourishment to support growth of beneficial SCFA-producing bacteria
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Increased production of key microbiome metabolites like butyrate and GLP-1 providing anti-inflammatory effects and improving insulin sensitivity
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Limiting excessive intake of animal proteins that are rich in BCAAs recently linked to metabolic impairment
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Oats contain a number of unique phytochemicals which provide relevant bioactivities influencing glucose regulation or inflammation
The research suggests consistency matters most – frequent low to moderate intakes spread regularly throughout each day may be ideal for maintaining steady production of SCFAs by microbe populations. Occasional large boluses trigger rapid fermentation and diarrhea for some.
I encourage those struggling with elevated blood sugars, insulin resistance or diabetes to give incorporating more whole oats and other minimally processed grains an honest 1 month trial in combination with tracking key biomarkers like HbA1c and fasting glucose. Monitor for benefits before concluding if this simple non-pharmacological strategy provides noticeable advantages.
Given the extraordinary turnarounds reported by skeptical doctors over a century ago when experimenting with the oatmeal cure diet, perhaps we shouldn’t be so surprised this traditional wisdom still has relevance backed by modern scientific understanding!