Olyphant used to be known for dramatic roles like on Deadwood and Justified, but he's always been immensely skilled with comedy and gets to really showcase that here. Jokes are spread throughout the cast, but Joel gets a heavy heap of one-liners. And the beauty of Santa Clarita is that a one-liner is rarely a punchline; more often than not, it's Joel or someone else commenting on the absurdity of the situation or impracticality of a plan.
DASH researchers studied three different diets on 459 people (27% of subjects had high blood pressure; the rest had normal). Keeping sodium levels constant (3,000 milligrams each day) they compared the traditional American diet (high in total fat, low in potassium, magnesium and calcium) to a diet high in fruits and vegetables (still not ideal in calcium or fat levels) and to a combination diet (the DASH diet - high in fruits, vegetables and low fat dairy foods and also low in total fat from animal products).
DASH was first introduced at a meeting of the American Heart Association in 1996 and later published in the New England Journal of Medicine in 1997.  The DASH trial randomly assigned 456 people to different diets to test the effects of dietary patterns on lowering blood pressure. The authors surmised that eating a diet with many different foods with blood pressure-lowering nutrients would show a greater effect on blood pressure than eating single nutrients, such as found in supplements or in a limited diet. Three diets were tested: 1) a control diet, or a standard American diet, 2) a fruits and vegetables diet, similar to the control diet but providing more fruits and vegetables and less snacks and sweets, and 3) a combination diet rich in fruits, vegetables, nuts, and low-fat dairy foods with reduced amounts of saturated fat, total fat, and cholesterol. The last two diets were richer in nutrients associated with lower blood pressure, such as potassium, magnesium, calcium, fiber, and protein. All three diets provided about 3000 mg sodium, which is more than the recommended amount from the Dietary Guidelines for Americans but less than the average sodium intake for Americans. 
Who actually created this diet? I can’t find any data on its development, much less any studies on its effectiveness or healthfulness. All of this supports my initial gut instinct that this diet has zero backing in science and health. Also, this diet appears to masquerade under several different names, the Cardiac Diet being one. Search both Cardiac and Military diets, and you’ll find the exact same three-day menu and protocol, although the Cardiac Diet is suggested to be a diet that physicians prescribe to obese patients for quick weight loss.
The South Beach Diet was developed in the mid-1990s by celebrity doctor Arthur Agatston with the assistance of Marie Almon, the former chief dietitian at Mount Sinai Medical Center in Miami Beach, Florida. Originally called the Modified Carbohydrate Diet, the plan was renamed the South Beach Diet after the South Beach neighborhood in Miami Beach near Agatston's practice.
Also, because the diet limits carbohydrate consumption, it could have some additional beneficial effects: David Ludwig, MD, PhD, a professor in the Department of Nutrition at Harvard T.H. Chan School of Public Health, noted in a post on the Harvard School of Public Health site that “fad diets” like South Beach and Atkins can, by helping limit the amount of processed carbs people eat, produce tangible health benefits for people backed up by sound scientific reasons. (6) That’s because the quickest way to stabilize blood glucose and lower insulin levels is to reduce carb intake, he says.