Nutrition-wise blog

Junk food diet for weight loss?

By Jennifer K. Nelson, R.D., L.D. and Katherine Zeratsky, R.D., L.D. November 18, 2010

It's an age old question, "What's the best way to lose weight?" A professor of human nutrition at Kansas State University is trying to answer this question. He just finished a 10-week junk food diet of chocolate-covered snacks, cream-filled cakes, sugary cereals, cookies and chips. For good measure, each day he also threw in a protein shake, a few veggies and a vitamin/mineral supplement. He's posted his results on Facebook.

I confirmed the nutrient analysis of a sample daily menu of this junk food diet from his Facebook page:

  • 1,600 calories (he tries to stay under 1,800 calories a day)
  • 232 grams carbohydrate (56 percent of total calories)
  • 60 grams fat (33 percent of calories)
  • 44 grams protein (11 percent of calories)
  • 25 grams saturated fat (14 percent of calories)
  • 110 mg cholesterol
  • 1,290 mg sodium

Here's my professional take on this junk food diet:

  • Calories. He's eating 800 to 1,000 calories a day fewer than what he needs.
  • Diet type. The percentages of carbohydrate, protein and fat classify this diet as "balanced" in these three energy-providing nutrients. It's not a high-protein diet.
  • Nutrient quality. It's anything but balanced. His food choices leave much to be desired. Carbs are mostly sugar. Saturated fat is double that recommended by experts. Protein is mostly from refined grain, although a glass of milk and a protein shake also provide protein. The main source of vitamins, minerals and other essential nutrients is a multivitamin and mineral supplement.

Preliminary medical results are rolling in and are looking good:

  • A 27-pound weight loss over 10 weeks
  • Body mass index now in the normal range (24.9)
  • Total body fat reduced from 33.4 to 24.9 percent (between 18 and 24 percent is good for men)
  • Total cholesterol reduced from 214 to 184 mg/dL (less than 200 is desirable)
  • LDL "bad" cholesterol went from 153 to 123 mg/dL (less than 100 is optimal)
  • HDL "good" cholesterol went from 37 to 46 mg/dL (60 or more is the target)

How can this be? He's eating junk!

Being overweight and "over-fat" are linked to high LDL and total cholesterol and to low HDL cholesterol. In contrast, a leaner body composition allows for improvement in blood fats. Similarly, other health markers such as blood sugar and blood pressure tend to improve with weight loss.

This experiment is great confirmation for the calorie equation: Eat fewer calories than you need, and you lose pounds and your health parameters improve. However, the long-term effects of this type of weight-loss diet remain unclear, as the professor candidly admits.

I agree with the professor's comment that "there seems to be a disconnect between eating healthy and being healthy." He reflects that before he started this diet he was eating healthy but he wasn't healthy — now he's eating unhealthy but has better health parameters.

I see his point, but I can't endorse eating unhealthy in order to become healthier. My bottom line: Calorie restriction is fine but cut the junk calories not the nutrient-packed ones. What are your thoughts?

- Jennifer

Nov. 18, 2010