Browse the evidence

Serum bicarbonate levels below 27 mmol/L can effectively rule out Obesity Hypoventilation Syndrome (OHS) in obese patients with sleep-disordered breathing who have a low to moderate pretest probability (<20%) of having the condition.

If you are obese and have sleep apnea, your doctor can check your blood bicarbonate level. If it is below 27, it is very unlikely you have the serious breathing condition called OHS, and you might not need more invasive blood tests. If it is higher, you likely need further testing.

A 10-year intensive lifestyle intervention targeting weight loss and increased physical activity does not reduce the overall prevalence of cognitive impairment or probable dementia in overweight or obese adults with type 2 diabetes.

For adults with type 2 diabetes, a 10-year intensive lifestyle program focusing on weight loss and exercise did not reduce the overall risk of developing mild cognitive impairment or dementia compared to standard diabetes education. While the intervention successfully produced sustained weight loss and increased physical activity, these changes did not translate to a lower prevalence of cognitive impairment in this specific population. However, the intervention did improve other health metrics, suggesting that lifestyle changes remain important for general health even if they do not prevent cognitive decline in this context.

In high-risk type 2 diabetes patients, GLP-1 receptor agonists and SGLT2 inhibitors reduce major adverse cardiovascular events (MACE), heart failure hospitalization, and chronic kidney disease progression independently of baseline HbA1c levels.

If you have type 2 diabetes and are at high risk for heart or kidney problems, ask your doctor about GLP-1 receptor agonists or SGLT2 inhibitors. These drugs protect your heart and kidneys regardless of your blood sugar levels. This is a key shift in treatment guidelines for high-risk patients.

SGLT2 inhibitors are recommended for type 2 diabetes patients with heart failure with reduced ejection fraction (HFrEF) to reduce hospitalization for heart failure, MACE, and cardiovascular death.

If you have type 2 diabetes and heart failure, especially with reduced ejection fraction, ask your doctor about SGLT2 inhibitors. These drugs are proven to reduce hospitalizations for heart failure and cardiovascular death, offering protection beyond blood sugar control.

SGLT2 inhibitors are recommended for type 2 diabetes patients with chronic kidney disease (CKD) to prevent CKD progression, heart failure hospitalization, MACE, and cardiovascular death.

If you have type 2 diabetes and chronic kidney disease, ask your doctor about SGLT2 inhibitors. These drugs are proven to slow the progression of kidney disease and reduce the risk of heart failure and cardiovascular death, offering protection beyond blood sugar control.

GLP-1 receptor agonists are recommended for type 2 diabetes patients with established atherosclerotic cardiovascular disease (ASCVD) to reduce MACE, with the strongest evidence for dulaglutide.

If you have type 2 diabetes and established cardiovascular disease, ask your doctor about GLP-1 receptor agonists. These drugs are proven to reduce major adverse cardiovascular events, offering protection beyond blood sugar control.

Increased body mass index (BMI) is strongly associated with a higher risk of developing oesophageal adenocarcinoma, colon and rectal cancer in men, biliary tract system cancer, pancreatic cancer, endometrial cancer (premenopausal), kidney cancer, and multiple myeloma.

Maintaining a healthy body weight is a critical, evidence-based strategy for reducing the risk of several major cancers, including colorectal, pancreatic, kidney, and endometrial cancers. This is not just about aesthetics; it is a direct modifiable risk factor. For men, colorectal risk is particularly sensitive to BMI increases. For women, maintaining a healthy weight, especially before menopause, is crucial for endometrial health. Public health guidelines should target these populations for personalized prevention strategies.

Weight gain in adulthood is strongly associated with an increased risk of postmenopausal breast cancer in women who have never used hormone replacement therapy (HRT).

For postmenopausal women, especially those not using hormone replacement therapy, avoiding weight gain in adulthood is a key strategy for reducing breast cancer risk. Each 5 kg of weight gain is linked to an 11% higher risk. This highlights the importance of long-term weight management, not just immediate weight loss.

Waist-to-hip ratio (WHR) is strongly associated with an increased risk of endometrial cancer.

For endometrial cancer risk, where you carry weight is as important as how much you weigh. A higher waist-to-hip ratio is strongly linked to a 21% increased risk for each 0.1 increase. Focus on reducing central adiposity through diet and exercise, not just overall weight loss.

Metformin is the preferred first-line pharmacological monotherapy for type 2 diabetes, to be continued unless contraindicated.

If lifestyle changes alone don't control your blood sugar, metformin is the standard first medication. It is generally well-tolerated and effective. Take it as prescribed unless you have specific health reasons that prevent its use.

Antihistaminergic drugs, antipsychotics, fast-release melatonin, ramelteon, and phytotherapeutics are not recommended for insomnia treatment.

Avoid using antihistamines, antipsychotics, fast-release melatonin, ramelteon, or herbal supplements for treating insomnia, as they are not recommended by current guidelines.

Daily supplementation with 1 gram of n-3 fatty acids (460 mg EPA and 380 mg DHA) does not significantly reduce the risk of serious vascular events in patients with diabetes mellitus without established cardiovascular disease.

If you have diabetes but no known heart disease, taking 1 gram of fish oil daily (providing 460mg EPA and 380mg DHA) will not significantly lower your risk of heart attacks, strokes, or vascular death compared to taking a placebo. This large, long-term study suggests that routine supplementation with these specific doses is not an effective strategy for preventing cardiovascular events in this group.

SGLT-2 inhibitors and GLP-1 receptor agonists reduce all-cause mortality, cardiovascular mortality, non-fatal myocardial infarction, and kidney failure in patients with type 2 diabetes, with absolute benefits scaling with baseline cardiovascular and renal risk.

If you have type 2 diabetes, especially with existing heart or kidney risks, adding an SGLT-2 inhibitor or GLP-1 agonist to your current regimen significantly reduces your risk of dying from heart or kidney causes. The higher your baseline risk, the greater the absolute benefit. Discuss these specific drug classes with your doctor to leverage these organ-protective effects.

SGLT-2 inhibitors are superior to GLP-1 receptor agonists for reducing hospital admissions for heart failure, while GLP-1 receptor agonists are superior for reducing non-fatal stroke.

Choose your diabetes drug based on your specific health history, not just blood sugar. If you have heart failure, an SGLT-2 inhibitor offers superior protection. If you have a history of stroke, a GLP-1 agonist is likely the better option. Ask your doctor which class aligns with your specific risks.

Monthly high-dose vitamin D3 supplementation (200,000 IU initial, then 100,000 IU monthly) does not prevent cardiovascular disease in the general population.

Taking 100,000 IU of Vitamin D3 once a month will not prevent heart disease or stroke, even if you are deficient. While maintaining adequate Vitamin D levels is important for bone health, this specific high-dose monthly regimen has not been shown to reduce cardiovascular risk in older adults. Do not use Vitamin D as a substitute for standard cardiovascular prevention strategies.

Resmetirom is a recommended pharmacotherapy for adults with non-cirrhotic MASH and significant liver fibrosis (stage ≥2), demonstrating histological effectiveness on steatohepatitis and fibrosis.

If you have advanced liver scarring (fibrosis stage 2 or higher) but not cirrhosis, ask your doctor about resmetirom, a medication that can improve liver health.

Bariatric surgery is an option for individuals with MASLD and obesity.

If you have obesity and MASLD, discuss bariatric surgery with your doctor as a potential option to improve your liver health.

There is no evidence that lifestyle interventions improve live birth, miscarriage rates, or menstrual regularity in women with PCOS.

Current evidence does not show that lifestyle changes improve menstrual regularity or fertility (live birth) in women with PCOS. While weight loss is beneficial, it should not be relied upon to restore regular cycles or ensure pregnancy.

Body Mass Index (BMI) is a primary mediator for the protective effect of physical activity on endometrial cancer, as adjusting for BMI eliminates the association, whereas it has limited effect on other cancer types.

For endometrial cancer prevention, maintaining a healthy BMI is likely the most critical factor, as the independent benefit of exercise appears to be mediated by weight. However, for other cancers like colon and breast, exercise provides protection even after accounting for BMI. Do not skip exercise thinking you are 'thin enough' to be safe from all cancers.

Caffeine consumption alters sleep architecture by increasing the duration and proportion of light sleep (N1) and decreasing the duration and proportion of deep sleep (N3/N4).

Even if you don't feel tired, caffeine may be stealing your deep sleep. Expect about 11 minutes less deep sleep and 6 minutes more light sleep per night if you consume caffeine close to bedtime. This reduces the restorative quality of your sleep, contributing to next-day fatigue.

Caffeine increases sleep onset latency by approximately 9 minutes and wake after sleep onset by approximately 12 minutes.

Caffeine makes it harder to fall asleep and stay asleep. Expect to take about 9 minutes longer to fall asleep and spend 12 minutes more awake during the night. This fragmentation reduces overall sleep efficiency by 7%.

There is inconclusive evidence regarding the effect of physical activity on the prevention of sarcopenia in older adults.

While evidence is inconclusive, engaging in physical activity, particularly resistance and functional exercises, is likely beneficial for maintaining muscle strength and performance, which are key aspects of sarcopenia.