Dr. Ohan Karatoprak (2026)

21/08/2021

CAROTENOIDS AND PREVENTION OF COGNITIVE DECLINE
Carotenoids are naturally occurring pigments found in yellow, orange, and dark green vegetables and fruits.
There are 6 major carotenoids found in human blood and brain.
Lutein, Zeaxanthin, Lycopene, alpha carotene, beta carotene, and beta cryptoxanthin.
A growing literature suggests that carotenoids play a role in the prevention of cognitive decline and Alzheimer Disease with their antioxidant and anti-inflammatory properties.
A recent study both from the USA and China ( 927 elderly with an average of 7 y of follow up.) evaluated the association of Carotenoid intake and risk of incident Alzheimer Disease. Higher intake of total carotenoids was associated with a 48% reduction in the rate of Alzheimer Disease. (Intake of carotenoids 24.8 mg/d compared to 6.7 mg/d)
CONCLUSION: Carotenoid intake was significantly associated with lower risk of developing dementia and Alzheimer Disease.

CAROTENOIDS AND PREVENTION OF SARCOPENIA
Sarcopenia is defined as the presence of age-related declines in muscle strength, muscle quality/quantity and physical function.
Oxidative stress is the central mechanism of age-related decline in muscle mass and function.Lower antioxidant serum concentrations have been linked to declines in muscle mass and physical function in older adults.
A study done by Harvard Medical School(more than 4500 adults aged 33 y-88 y with 12 year follow-up)) concluded that Higher Carotenoid intake decreases the oxidative stress with their ANTIOXIDANT effect and increases GRIP STRENGTH and improves GAIT SPEED.

Major sources of carotenoids are: Tomatoes, tomato juice, tomato paste, carrots, yams/sweet potatoes, squash and green leafy vegetables like kale and spinach.
Non Vegetable source: Egg yolk
One medium carrot, one medium tomato, one cup of kale/spinach in the salad and one egg a day keeps Alzheimer Disease away!
(Avoid the Antioxidant supplements. They might increase the risk of Lung Cancer especially in smokers!)

12/08/2021

Alcohol, Read Meat and Colon Cancer
Recently a review of findings of 45 research projects by the University of Utah College of Pharmacy showed that; People with high alcohol consumption or high red meat consumption had approximately 60% and 10% higher odds of developing Colon Cancer respectively, compared those with lower or no alcohol or red meat consumption. The findings also revealed that individuals with a high intake of Dietary Fiber(fruits, vegetables, legumes and whole grains), Calcium and Yoghurt intake had 20% lower Colon Cancer risk.
How much alcohol is safe?
According to other studies about alcohol and the risk of breast cancer and prostate cancer:
Women 3 drinks a week, men 7 drinks a week.( a can of beer, 5 ounce of wine and 1.5 ounce of hard liquor is a drink!)

Dietary pattern and Progression of Knee Osteoarthritis
A recent study from Harvard Medical School and Brown University researchers; Adherence to western Dietary pattern was significantly associated with radiographic and symptomatic progression of knee osteoarthritis.
According to this study, reducing the consumption of unhealthy western diet high in French fries, red and processed meats, poultry, refined grains, sugar-containing beverages and foods and pizza, while increasing consumption of a healthy prudent diet high in fruits, vegetables, legumes, whole grains and fish may slow knee osteoarthritis progression.

31/07/2021

DIETARY FIBERS AND CARDIOVASCULAR DISEASE.

A recent study(Global Burden of Diseases) concluded that suboptimal diet is responsible for more deaths than any other risk factors globally, including to***co smoking.
Mounting evidence suggests that dietary fibers exert a protective role against various chronic diseases. Dietary fiber intake is still far below recommended levels in many western countries, including the USA and they represent a promising target in suboptimal diet consumption. Fibers help postprandial(after eating) blood sugar control, by slowing down digestion. Fibers help you feel satisfied. They alter gut metabolism and stimulate mucus formation necessary for healthy bacteria..
Recently a study conducted in France and USA assessed the association between the intake of Dietary Fibers(soluble and insoluble) and from different sources like fruits,vegetables, legumes, whole grains and tubers(tubers are potatoes, sweet potatoes, yam, jerusalem artichoke) and risk of Cardiovascular disease(CVD), type-2 diabetes, cancer and mortality. More than 100.000 participants were followed over five years.
Conclusion of this study was: Higher intake of Dietary Fibers, especially soluble fibers and fibers from fruits was inversely associated with the risk of several chronic diseases(CVD, type-2 diabetes, cancer) and with mortality.

We should eat plenty of fruits, vegetables and legumes(beans, lentil, chickpeas). Compared with other dietary fiber sources, legumes contain the highest levels of resistant starch. They slow digestion through the stomach and small intestine and provide beneficial soluble and insoluble fibers to the large intestine. Like fruits and vegetables , legumes are also rich in vitamins, minerals and phytochemicals.

21/07/2021

ULTRA-PROCESSED FOOD CONSUMPTION AND THE RISK OF SHORT TELOMERES

Telomeres [from the Greek words Telos(end) and Meros(part)] are located at the both ends of chromosomes. They are involved in the protection of DNA in the chromosomes. Telomeres get shorter throughout the lifespan. Thus telomere length is a marker of biologic age. Oxidative stress and inflammation are the mechanisms associated with telomere shortening and therefore shorter lifespan.
Regarding dietary patterns, globally Ultra-processed-food(UPF) consumption is increasing and fresh-food consumption is decreasing. UPFs are industrial formulations of food derived substances(oils, fats, sugars, starch, protein isolates) that contain little or no whole-foods and often include flavorings, colorings, emulsifiers and other cosmetic additives.(these can increase insulin resistance and cause weight gain!). They are assembled ready-to-eat palatable foods with low nutritional quality.
UPFs have been associated with several diseases such as high blood pressure, obesity, metabolic syndrome, depression, type-2 diabetes, cancer and all-cause mortality(increases the risk of death from many diseases). These age-related diseases are also related to oxidative stress and inflammation like telomere shortening and therefore causing shorter lifespan.
Some studies found associations of sugar sweetened-beverages, alcohol consumption, processed meats and other foods rich in saturated and trans fats and sugar with shorter telomere.
Recently a study from University of Navarra, Department of Nutrition, Spain and Harvard School of Public Health, Boston MA, evaluated the association between UPF consumption and the risk of having short telomeres in 886 participants aged 51-91 y , followed between 1999-2018.
Conclusion of this study: Higher consumption of UPF(> 3 servings/d) was associated with higher risk of having shorter telomeres.
The list of UPFs causing shorter telomere in this study
Carbonated drinks, sweet and savory packaged snacks, ice-cream, candies, mass-produced packaged breads and buns, margarines and spreads, cookies, pastries, cakes, breakfast cereals, energy bars, energy drinks, fruit yogurts, fruit drinks, cocoa drinks, meat and chicken extracts, instant sauceses, slimming products such as powdered of fortified meal substitutes, many ready -to -eat products including fish and chicken "nuggets", sausages, burgers, hot dogs, and other processed meat products, powdered and packaged "instant" soups, noodles and deserts.
SHORTER TELOMERE=SHORTER LIFESPAN!
We should avoid all of the above UPFs

The good news is: Telomere length can be modified with good nutrition(fruits, vegetables, legumes, nuts and seeds, fish, regular Greek yogurt!!) and physical activity.

24/03/2021

GUT MICROBIOME, ANTHOCYANIN INTAKE AND ABDOMINAL FAT(VISCERAL FAT)

There is growing evidence that the gut-microbiome(digestive tract associated microbes, more than 1000 species) plays an important role in our health and disease.
Gut-microbiome is involved in digestion, metabolism, nutrition and immune function. imbalance of gut-microbiota is linked to many diseases such as coronary artery disease, type-2 diabetes, inflammatory bowel disease, obesity and neurological diseases such as parkinson disease and multiple myeloma.
The greater diversity of gut-microbiome is important for good health(Mediterranean diet will give you a good gut-microbiome diversity). Gut-microbiome plays an important role in the bioactivity of flavonoids. As you know flavonoids are a diverse range of bioactive compounds present in many fruits, vegetables, herbs, grains, tea and wine.
There are 6 flavonoids subclases (flavonols, flavones, flavanones, flavan-3-ols, flavonoid polymers and anthocyanins). Anthocyanins are extensively metabolized in the gut and epidemiological evidence indicates strong association between higher anthocyanin intake and improved measures of body fat.
Recently researchers from Norwich Medical School, Norwich, United Kingdom examined the association between dietary intakes of flavonoids, the gut-microbiome and MRI measured VAT(visceral abdominal fat) and SAT(subcutaneous abdominal fat). Study included 618 men and women aged 25-83 y. They had dietary assessments, blood tests, stool tests for gut-microbiome and body MRI for VAT and SAT measurements. Participants were followed for 7 years.
Conclusion of this study: Participants with the highest intake of food rich in anthocyanins(68.7mg of anthocyanins, equivalent to 1/3 of a cup of blueberries) had greater diversity in their gut-microbiome(which is important for good health) and lower abdominal fat(VAT):

Anthocyanin rich foods are: Blueberries, strawberries, blackberries, red currants and red wine.

06/03/2021

Eggs do not increase the risk for cardiovascular disease.
In three large international studies including 177,000 individuals from 50 countries in 6 continents, did not find significant associations between moderate egg intake(one egg a day) and blood lipids(cholesterol profile) and Cardiovascular disease events.
Eggs are a rich source of high-quality protein, minerals, B-vitamins, fat-soluble vitamins(A,E,D and K vitamins) and bioactive compounds such as lutein and zeaxanthin(for prevention of age related macular degeneration).
Enjoy your eggs

Refined carbohydrates and infertility:
Approximately 10-15% of couples experience infertility.
Study from Denmark:
Among women attempting to conceive in Denmark and North America, diets high in refined carbohydrates and added sugar and low in fiber was associated with modestly reduced fecundability.
Decrease your refund carbohydrate and added sugar intake and have high fiber diet.(fruits, vegetables, legumes, whole grain bread, crushed flax seeds

Multinational study:
Higher nut intake was associated with lower mortality risk from both cardiovascular and noncardiovascular causes in low-income, middle-income and high-income countries.(Eat your mixed nuts and seeds for longevity!)

14/02/2021

KNOW YOUR MEASUREMENTS!

WC(waist circumference)
WHtR(waist/ height ratio

Measures of CENTRAL ADIPOSITY (Abdominal Fat, Visceral Fat which can be measured with Waist Circumference and Waist Height Ratio besides imaging with MRI or DEXA)) is associated with increased risk of All-Cause mortality(heart disease, cancer, type-2 diabetes etc.) according to the new study from BJM(British Journal of Medicine).
The researchers found that "regardless of BMI(body mass index)", Increased Waist Circumference and Waist Height Ratio, increase the risk of All-Cause mortality both for men and women.

Visceral Fat(abdominal fat) which gathers around the internal organs as people gain excess weight, is more dangerous than regular subcutaneous fat(fat under the skin). Visceral fat(abdominal fat) is linked to higher risk of heart disease, type-2 diabetes, both men and women and breast cancer in women. It has been also connected to an increased risk of dementia and overall a shorter lifespan.

Normal Waist Circumference(WC): 31.5 inch and less for women
37 inch and less for men
(put the tape measure on your belly button and measure abdominal circumference)

Normal Waist to height ratio(WHtR): Same for both women and men and is between 0.4-0.5(ideal). More than 0.59 is abdominal obesity(excessive abdominal fat)
(measure your waistline and divide it to your height.)
For example waistline is 32 inch and height is 66inch
32:66= 0.48
Watch your waistline! KEEP YOUR WAIST LINE LESS THAN HALF OF YOUR HEIGHT!
(With a piece of string measure your height, then fold the string in half and check to see whether it fits around your waist!)

Happy Valentine's Day

07/02/2021

This week I came across an interesting article about obesity and genetics that I would like to share with you.
As we know, weight gain and obesity(excess body weight) is a very complex condition caused by four important factors.
HORMONAL (insulin resistance, leptin resistance are few among many other hormone imbalances)
METABOLIC (low calorie burning capacity of the body and Metabolic Syndrome)
BEHAVIORAL (sedentary life, processed fast food intake, excessive sugar intake , staying on a low calorie diet for long time, emotional factors)
GENETIC (one or both parents being obese),
We can help ourselves and correct the first 3 factors(causes )by proper exercise, eating healthy food and enough calories for good metabolism, taking some supplements(pre/probiotics) to support our intestinal microbiome for weight management and good health and solving the emotional factors.
How about the fourth one, the GENETIC factor in obesity? How can we change our genes?
We cannot change our genes but we can change their activity!! We can make our genes active or passive with our lifestyle change!(Epigenetics).
Here is the study conclusion from School of Public Health (Harvard Medical School, Boston, MA, and Peking University from China):
Long chain n-3 PUFA (polyunsaturated fatty acid) intake may modify the genetic associations with weight change. FISH is the primary food source of PUFAs.
Higher intake of FISH and long chain n-3 PUFAs are associated with an attenuation of the genetic association with long term weight gain.
Eat your fish, and take your omega-3 fish oil supplement for weight management. (Don't eat fried fish. Fried fish has no benefit!) Fish is not good only for weight management, but also is good for inflammation and vascular health.

31/01/2021

CRUCIFEROUS vegetables are good for cancer prevention.(cruciferous name comes from latin, means "cross-bearing" from the shape of their flowers, whose four petals resemble a cross).

Cabbage
Cauliflower
Broccoli
Brussel sprouts
Kale
Bok choy
Arugula
Turnip
Radish
Watercress
Onion
Garlic
They contain sulfur compounds and indol which are essential components of DNA repair enzymes.(superoxide dismutase and glutathione peroxidase) and they inhibit colorectal, bladder, lung, mouth,throat,stomach prostate and breast cancers.

A recent study from the United Kingdom showed that sulforaphane(sulfur compound) rich broccoli soup for one year affected gene expression in the prostate of men with early prostate cancer and reduced the risk of cancer progression.
(broccoli sprouts are loaded with cancer preventing sulfur compounds!)

24/01/2021

Today I am going to share a study which analyzed the "Carbohydrate Quality" and changes in Cardiovascular Disease(CVD) risk factors such as Hypertension, Lipid profile, Type-2 diabetes, Waist circumference and Obesity. Carbohydrate Quality in our diet is very important for overall health, weight loss and its maintenance. A large body of evidence has demonstrated that QUALITY of dietary carbohydrate rather than their QUANTITY is a major determinant of CVD and All-cause mortality.
"Carbohydrate Quality" is 1-Low glycemic index/low glycemic load foods , 2-High dietary fiber, 3-whole grains, 4- Avoidance of liquid carbohydrates(soda, fruit juice etc.) and reducing added sugars.
An example for Glycemic Index: Whole grain rice is a fiber-rich food but does contain a mid-to-high glycemic index(avoid high glycemic index foods!), whereas legumes are also
fiber-rich food but contain a low glycemic index.(get familiar with low glycemic index foods! and include them in your diet)

Researchers in Spain examined 6 and 12 month changes in Carbohydrate Quality and concurrent changes in several CVD risk factors in PREDIMED-PLUS study(this study was intensive weight loss and lifestyle intervention program with a calorie reduced Mediterranean diet). Overweight and obese adults(aged 55-75 years)with Metabolic Syndrome were in this study.
During 12 months follow up, the majority of participants improved their
"Carbohydrate Quality" by INCREASING their consumption of Fruits, Vegetables, Legumes, Fish and Nuts and DECREASING their consumption of refined cereals, white bread, added sugars,and sugar-sweetened beverages(diet beverages are as bad if not worst!).
After 6 months, Body weight, Waist circumference, Blood pressure, Fasting blood sugar, HgA1c and triglyceride levels DECREASED with improved Carbohydrate Quality. After 12 months improvements were additionally observed for total cholesterol and HDL(good) cholesterol.

"To lose weight, to decrease waist circumference and to decrease the risk factors for cardiovascular disease we need to improve our CARBOHYDRATE QUALITY even though we are following the healthy Mediterranean Diet. Quality of carbohydrate is more important than the quantity.

18/01/2021

NUTS AND CARDIOVASCULAR HEALTH
Walnuts, cashews, pistachios, almonds and hazelnuts are top 5 most-consumed tree nuts globally. We know that nuts are good for cardiovascular disease. (UN ROASTED).
When 10 common food groups [whole grains, legumes, nuts, fruits, vegetables, eggs, dairy, fish (healthy) and red meat , refined grains, sweetened soft drinks(unhealthy)] and their benefits for cardiovascular disease were investigated in a 2018 study, NUTS was ranked the best for cardiovascular disease prevention. Pistachios and walnuts are the best among nuts for lowering LDL cholesterol and triglycerides.

GUT HORMONES FOR BLOOD SUGAR REGULATION AND WEIGHT LOSS
Secretion of GLP-1(glucagon like peptide) and PYY hormones from the small intestine after eating is important for appetite suppression, blood sugar control, insulin regulation and for weight loss. Green leafy vegetables, legumes, plant roots such as artichoke and leeks, fruits with skin and fibers such as psyllium, all increase the secretion of GLP-1 and PYY hormones.( we should have these food for good health and weight control)

10/01/2021

Here is an interesting article about prebiotics and their effects on intestinal bacterias, intestinal hormones and desiring healthy food and appetite control.

INULIN-RICH VEGETABLES, GUT HEALTH AND APPETITE CONTROL

For several years the gut microbiota(good and bad bacteria in our intestine) has been pointed out as an important ecosystem that plays a key role in human physiology. Alteration of gut microbiota composition has been associated with many conditions such as type 2 diabetes, obesity, neurological diseases such as parkinson disease, autism, Irritable bowel disease and behavioral disorders.
In the diet some non digestible carbohydrates called PREBIOTICS( inulin-type fructans) are fermented by gut microbiota, has been shown to cause positive health effects, such as improvement in intestinal permeability, a decrease in fat mass, an increase the production of intestinal hormones(glucagon like peptide-1, PYY) acting on satiety and improvement of appetite control by changing gut microbiota. Inulin-type fructans(ITF) mostly occur in plant roots, such as Jerusalem artichokes, artichokes, leeks, onion, garlic, and salsify.
Recently researches from Belgium(with the participation of several universities) evaluated the impact of consuming inulin-type fructan rich (ITF-rich)vegetables (prebiotic) daily on gut microbiota, gastrointestinal symptoms, and food-related behaviour in healthy individuals.
Participants were given ITF-rich vegetables for two weeks in a controlled diet. Nutrient intake, food-related behaviour, f***l microbiota composition and gastrointestinal symptoms were assessed before and after two weeks of special diet and three weeks after returning to their usual diet.

CONSUMING ITF-RICH VEGETABLES FOR TWO WEEKS LED TO INCREASED SATIETY AND REDUCED DESIRE TO EAT SWEET, FATTY AND SALTY FOOD.

Three weeks after participants returned to their usual diet, these effects were further strengthened, and the desire to eat very sweet and fatty food was significantly decreased. (the calorie intake was not changed throughout the study).
In this study the high intakes of fructans in the diet was well tolerated and contributed to appetite regulation and reduction to desire to eat unhealthy food.(sweet, fatty and salty food).

You can incorporate the fructan rich items(Jerusalem artichokes, artichokes, leeks, onion, garlic) in your diet.

Dr. Ohan Karatoprak