Even lean people run a risk — one that certain supplements seem to reduce
One in 10 Americans — nearly 30 million — have diabetes.
Almost all diabetics suffer from the type-2 form. Despite its common name — “adult-onset” diabetes — it increasingly afflicts children and young adults.
A small minority of Americans suffer from type-1 or “juvenile” diabetes, which is an autoimmune disease that severely damages the body’s ability to produce insulin.
Type-2 diabetes is the leading cause of premature deaths, and it’s characterized by chronically elevated blood sugar levels (hyperglycemia).
Chronically high blood sugar levels occur because the body can’t make enough insulin, and/or because its insulin no longer controls blood sugar levels effectively — a condition called insulin resistance.
These are some of the alarming consequences of undiagnosed, untreated diabetes:
- Heart attack
- Kidney disease
- Nerve damage
- Heart disease and related death
- Blindness and other eye problems
- High blood pressure (hypertension)
Luckily, even minor changes in lifestyle can greatly reduce the risk of developing diabetes.
There’s good evidence that maintaining robust vitamin D blood levels helps deter diabetes.
And recent findings suggest that multivitamins and seafood-source omega-3 fatty acids may boost the anti-diabetes benefits of vitamin D.
Omega-3s and a multi may boost effectiveness of vitamin D for diabetes
Thisa Canadian study probed the effects of supplemental vitamin D plus multivitamins and omega-3 fatty acids on the risk of diabetes.
It also examined the potential for this supplemental regimen to reverse the progression of this disease.
The study was led by researchers from the University of Alberta and the University of Calgary and included 1,018 clients of Pure North — a non-profit center that helps Canadians stay healthy through preventive measures.
For most adults, diabetes follows a predictable (and negative) course: diagnosis and treatment, followed by more and more health complications and loss of abilities.
In short, the results showed that vitamin D — combined with a broad-spectrum multivitamin-mineral supplement and omega-3 fatty acids — may slow or even stop this crippling progression toward premature death.
The participants were divided into two groups, each assigned to a different daily regimen:
- Vital 1 group — Vitamin D drops plus a limited multivitamin formula.
- Vital 2 group — Vitamin D drops plus a more complete multivitamin/mineral and an omega-3 fatty acid supplement.
Only people assigned to the Vital 2 group — vitamin D plus a complete multivitamin plus omega-3s — enjoyed healthier blood sugar and inflammation levels.
During the 12-month study, 44% of the Vital 2 group moved from pre-diabetes/diabetes to a more normal blood sugar status, compared with only 8% of the Vital 1 group.
Better yet, the improvements were still being enjoyed by the Vital 2 group two years later.
As the researchers wrote, “The combination of nutritional supplements taken by the Vital 2 participants was associated with a reduced risk of progressing from normoglycemia [normal blood sugar] to prediabetes [chronically elevated blood sugar] and an increased likelihood of a prediabetic participant improving to normoglycemia, changes that were sustained at two years after program entry.”
And they made this important point: “If the results observed in this natural experiment could be replicated across a larger population, it could represent a highly cost-effective option for reducing diabetes risk.”
Fish oil alone helps fight diabetes
Previous research indicates that, by themselves, supplemental omega-3s can have a positive impact (Wu JH et al. 2013).
A 2013 “meta-analysis” found that omega-3 fish oil supplements can boost the levels of adiponectin: a hormone that’s been linked to reduced risks for diabetes and heart disease.
Adiponectin exerts positive effects on metabolic processes, including control of blood sugar and inflammation.
Previous long-term human studies have linked higher average levels of adiponectin reduced risks for type-2 diabetes as well as coronary heart disease (which is promoted by diabetes).
The meta-analysis melded together the results of 14 placebo-controlled clinical trials that included more than 1,200 participants.
In each of these clinical trials, half of the participants were given fish oil, while half were given placebos such as sunflower or olive oil.
Overall, the participants who took fish oil daily experienced a modest rise in their adiponectin levels — an increase that could produce beneficial effects over time.
Co-author Jason Wu, Ph.D., of the Harvard School of Public Health, said this: “By reviewing evidence from existing randomized clinical trials, we found that fish oil supplementation caused modest increases in adiponectin in the blood of humans.”
Professor Wu added this clarification: “Although higher levels of adiponectin in the bloodstream have been linked to lower risk of diabetes and coronary heart disease, whether fish oil influences glucose metabolism and development of type 2 diabetes remains unclear. However, results from our study suggest that higher intake of fish oil may moderately increase blood level of adiponectin, and these results support potential benefits of fish oil consumption on glucose control and fat cell metabolism.”
Fishy diets also linked to lower diabetes risk
Omega-3s fatty acids in fish may also help prevent adult-onset diabetes.
A Spanish study examined the dietary patterns of 945 men and women at high risk for heart disease, who ranged in age from 55 and 80.
The goal of the study was to look for any links between meat and fish consumption and known cardiovascular risk factors (Mercedes-Prieto S et al. 2011).
The Spanish team’s analysis showed that people who ate more omega-3-rich fish were less likely to have diabetes and enjoyed lower blood sugar levels.
In contrast, people who ate lots of red meat — especially cured meats — were more likely to be overweight or obese.
The study's leader, Mercedes Sotos Prieto of the University of Valencia, proposed a possible explanation: “The increase of omega-3 in the cells of the skeletal muscles improves insulin sensitivity.”
Likewise, a Finnish study found that high intakes of omega-3 fatty acids from fish may help lower the risk of type-2 diabetes (Virtanen JK et al. 2014).
The findings came from analysis of data from a large-scale study from the University of Eastern Finland, called the Kuopio Ischaemic Heart Disease Risk Factor Study (KIHD).
For their analysis, the team first looked at the levels of omega-3 fatty acids in the blood of 2,012 men whose ages ranged from 42 and 60 years.
Follow-up work was done around 19 years later, at which time 422 men had been diagnosed with type-2 diabetes.
The participants were split into four groups based on their levels of omega-3 fatty acids from either dietary fish or omega-3 fish oil supplements — and the men with the highest omega-3 blood levels were 33% (one-third) less likely to develop diabetes, compared to the group with the lowest levels.
As the Finns concluded, “A well-balanced diet should include at least two fish meals per week, preferably fatty fish. Fish rich in long-chain omega-3 fatty acids include wild salmon, herring, anchovy, sardines, and mackerel.” For more on that study, see Omega-3s May Slash Men's Diabetes Risk.
Mercury in fish doesn't raise cardio risks
And, although dietary mercury has been linked to increased risks for cardiovascular disease, that does not seem to be the case for people at risk who eat lots of fish.
Last year, researchers from Harvard and Spain reported that people at high risk for heart disease — and who routinely ate lots of fish — did not suffer any higher cardiovascular risk due to fish-borne mercury (Downer MK et al. 2017).
That may be because — in almost all ocean fish — the amount of selenium outweighs the amount of mercury.
This maters because the damage caused by mercury relates directly to its strong propensity to bind with selenium in our bodies, making that essential element unavailable to build key "selenium-dependent" antioxidant enzymes.
For more on that, see Most Fish Rank as Very Safe on New, Selenium-Based Standard.
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