The Diet Detective: A Guide to High-Calorie, Nutrient-Dense Foods

I have a friend whose father has cancer, and she recently wrote to ask me what she could do to help him gain weight and strength. Not really my area, since I generally help people lose weight in order to live healthier lives. 

But the part about "healthier lives" struck a nerve.  I realized that whether you're gaining weight or losing weight, many of the health issues are similar. So I decided to look at foods that are still healthy even though they pack a huge calorie punch!  You should eat them, but if you're watching your weight, keep the portions small.

More: 15 Foods for a Healthy Diet

Nuts

Why: Nuts are a great source of protein and fat. The Nurses' Health Study followed 86,016 nurses over the course of 14 years and found that those who ate 5 ounces or more of nuts per week reduced their risk of death from heart attack by 35 percent and were on average thinner than those who did not eat nuts. Those who ate nuts a few times per week had a significantly lower risk for developing heart disease, and those who ate nuts five times per week or more showed a greater than 50 percent risk reduction as compared to those who did not eat nuts very often.

Nutritional Information:     

Almonds   
3 ounces (72 nuts)       
480 calories   
45 g fat   
18 g carbohydrates   
18 g protein

Brazil Nuts   
3 ounces (21 nuts)       
510 calories   
42 g fat   
24 g carbohydrates   
15 g protein

Cashews   
3 ounces (60 nuts)       
510 calories   
42 g fat   
24 g carbohydrates   
15 g protein

More: 3 Reasons to Eat More Fat

Walnuts   
3 ounces (42 halves)       
540 calories
51 g fat   
15 g carbohydrates
12 g protein

Pistachios, Shelled   
3 ounces (141 nuts)       
510 calories    
45 g fat   
6 g carbohydrates   
12 g protein   

More: Turn 5 Main Ingredients into 25 Dinners 

Pecans   
3 ounces (60 halves)       
570 calories   
60 g fat   
15 g carbohydrates   
9 g protein
    
Macadamia   
3 ounces (33 nuts)       
600 calories    
63 g fat   
12 g carbohydrates   
6 g protein   

Pine nuts         
3.5 ounces       
673 calories     
68 g fat
13 g carbohydrates
14 g protein

More: The Nut Case: Do They Have Too Much Fat?