A group of researchers from 5 major medical centers found that eating a specific diet rich in nutrient-dense fruits and vegetables, whole grains and low fat dairy can be a powerful tool in lowering blood pressure.
The DASH DIET( Dietary Approaches to Stop Hypertension) was found in 1996 to lower blood pressure about the same as a blood pressure medication would, and since that time has quickly become one of the most often prescribed diets in clinical practice today.
The DASH Diet is recommended by the American Heart Association, in the USDA's 2005 Dietary Guidelines for Americans, and is featured in the US High Blood Pressure Guidelines.
The DASH DIET Study 459 people were chosen to participate in the DASH DIET Study. They were randomly assigned to one of three different types:
·A diet with more fruits and vegetables, but otherwise similar to the typical American diet
·The “DASH diet” – rich in fruits, vegetables, and low-fat dairy products; moderate in fish, poultry, and nuts; and reduced in red meat, sweets, and sugar-sweetened drinks.
To assure they weren't doing anything else that might lower their blood pressure, participants were asked not to make any major changes in the physical activity levels during the study.
Participants were weighed frequently to make sure their weight stayed constant; if someone gained or lost weight, they were given a bit less or more food to eat to get their weight back to what it was.
Salt/sodium intake was the same in all three diets – slightly lower than the U.S. average, but still higher than what most guidelines recommended.
Those who ate the typical American diet did not see a change in their blood pressure.
Those on the fruit and vegetable diet experienced a significant lowering of their systolic blood pressure – The upper number, which is a measurement of blood pressure in the arteries when the heart contracts to pump out blood – but little change in their diastolic pressure.
But the men and women who ate the DASH DIET for eight weeks experienced a significant drop in both their systolic and diastolic blood pressure readings. Changes occurred within a week of starting the DASH diet, stabilized within two weeks, and stayed lowered for the remainder of the eight weeks.
On average, blood pressure fell 5.5 mmHg (systolic) and 3.0 mmHg (diastolic) among all participants (including both those with normal blood pressure and those with hypertension).
In participants with high blood pressure, blood pressure dropped an average of 11.4 mmHg (systolic) and 5.5 mmHg (diastolic).
These improvements in blood pressure are about the same as what can be achieved with a single antihypertensive medication.
There were positive health outcomes of the DASH diet beyond lowering high blood pressure.
Most importantly, perhaps, the DASH diet lowered the study participants'cholesterol levels.
When blood cholesterol is high, cholesterol and other fatty substances collect on the walls of your blood vessels and in time restrict or block the flow of blood to your heart.
High cholesterol, which is generally caused by a diet high in saturated fats, is a major risk factor for heart disease.
The DASH diet is low in total and saturated fat.
People who ate the diet during the study, dropped their cholesterol 14 points. The “bad” cholesterol (LDL) fell 11 points. The level of good cholesterol (HDL) also fell by 3.7 points (this type of drop in HDL is seen when people reduce their overall fat intake). Combining all the effects (changes in blood pressure, LDL, and HDL), there was an important improvement in overall cardiac risk with the DASH DIET.
A later study was done at the Boston University Medical Center, which offered the DASH Diet in an online form to employees of a large US company.
Over 4,000 people enrolled in the DASH DIET program.
They received weekly email reminders to log in to the site for information on topics such as weight loss, exercise, reading food labels, grocery shopping and more.
They also were encouraged to track the changes they made to their diet, exercise, weight and blood pressure online. After one year in the DASH DIET program, study participants
had lost weight and lowered their blood pressure significantly.
They started eating more fruits and vegetables and moved from higher fat dairy products to lower fat versions.
After the success of the DASH DIET program, the researchers decided to offer the program to the general population online at DASH DIET
The reason the researchers think that the DASH DIET is perfect for all Americans is that it doesn't take a whole lot of learning.