Examine publishes rigorous, unbiased analysis of the latest and most important nutrition and supplementation studies each month, available to all Examine Members. Click here to learn more or log in.
Study under review: The effect of caloric restriction on blood pressure and cardiovascular function: A systematic review and meta-analysis of randomized controlled trials
Introduction
One of the most prevalent and high-risk health conditions worldwide is hypertension, also called high blood pressure. Blood pressure (BP) refers to the pressure that the blood exerts on the arteries after the heart contracts (systolic blood pressure, SBP) or relaxes between beats (diastolic blood pressure, DBP). Under normal conditions, the arteries accommodate their diameter to the amount of blood that the heart propels. Hence, BP is determined by the amount of blood that the heart ejects and the resistance the arteries provide.
Alterations in the arterial wall[1], among other factors[2], can lead to increases in BP, which subsequently can start a cascade of events leading to an increased risk of cardiovascular disease and mortality, and constitutes one of the main causes of diseases in the modern world[3]. The most burdensome diseases caused by hypertension worldwide are shown in Figure 1. Hypertension is also associated with other prevalent comorbidities, such as obesity and diabetes, which produce additional problems and likely share[4] common pathological mechanisms.

Reference: Forouzanfar et al. JAMA. 2017 Jan.[5]
Calorie restriction (CR) is well supported[6] for the treatment and prevention of chronic, lifestyle- and aging-associated diseases. Since there is a tight link between hypertension and overweight and obesity, it is expected that CR would have an effect on BP by causing a reduction in bodyweight, and potentially[7] through other mechanisms[8].
The authors of the current study conducted a systematic review and meta-analysis of randomized controlled trials (RCT) testing the effects of CR on BP and cardiovascular function in humans.
Hypertension, or high blood pressure, is one of the leading causes of cardiovascular mortality in the world. Calorie restriction, which has strong scientific support for preventing chronic and lifestyle- and aging-associated diseases, might be an effective treatment for hypertension.
What was studied?
What were the findings?
The bigger picture
Frequently asked questions
What should I know?
Other Articles in Issue #71 (September 2020)
-
The key to berry low blood pressure
Berry supplementation drops blood pressure by a small but clinically significant degree, with cranberry, barberry, and cherry juices having a more clear impact than other fruits and forms. But some types and forms of fruit (especially whole fruits) weren't well-represented in this meta-analysis.
-
D-ribose for diminishing DOMS
D-ribose drops DOMS, but doesn't pack a punch performance-wise.
-
Deep Dive: Does eating less fat make us less fat?
How much does dietary fat intake impact bodyweight in people not actively trying to lose weight? Here, we cover a recent meta-analysis that explored this question.
-
Nulls: July-August 2020
A round-up of some recent nutrition and supplementation studies that didn't find any clear effect.
-
Supplementing saffron for rheumatoid arthritis relief
The first human trial examining saffron's effects on rheumatoid arthritis is promising on its face but has some study design issues that leave us concerned.
-
Deep Dive: Investigating the complicated relationship between potassium supplementation and blood pressure
Potassium supplementation can lower blood pressure in moderate doses, but this novel meta-analysis suggests that too much could have the opposite effect.
-
Mini: Evidence-based recommendations for reducing Alzheimer’s disease risk
We boil down the main takeaways from a recent systematic review exploring what people can do to reduce the risk of developing Alzheimer's disease.